Entering 2019, the Pirates seemingly had a solid long-term plan at catcher. Francisco Cervelli and Elias Diaz would once again split starts, reuniting arguably the game's best catching tandem in 2018. After that, Cervelli would likely sign elsewhere as a free agent and Diaz -- who showed unprecedented offensive potential in 2018 -- would be the man.
As we near August, and the Pirates languish closer to last place in the NL Central standings and fall further away in the wild card chase, that plan looks shot. For Cervelli, it's been recurring concussions — both player and team are concerned more for his long-term quality of life than his short-term career prospects. As for Diaz, he has devolved from a rare power-hitting threat behind the plate to a guy who has had difficulty getting the ball out of the infield. What's behind Diaz's 2019 power outage? Let's take a look.
As a minor leaguer who was considered a mid-level prospect, Diaz never displayed much power. His on-base plus slugging percentage (OPS) in the minors was a modest .686 in more than 2,500 plate appearances. In more than 750 PA at the Triple-A level, Diaz had a .668 OPS. Considering his struggles as a rookie with the Pirates in 2017 -- his park-and-league-adjusted OPS was 47 percent worse than the overall MLB average (53 OPS+) -- and his relatively advanced age for a prospect, Diaz looked like a career backup.
And then, he started raking. In 277 trips to the plate in 2018, the Venezuelan backstop hit 10 home runs and posted an adjusted OPS that was 14 percent better than the MLB average (114 OPS+). Diaz boasted the sixth-highest OPS+ among all catchers who had at least 200 PA, trailing only J.T. Realmuto (130 OPS+), Wilson Ramos (130), Cervelli (123), Yasmani Grandal (120) and Omar Navarez (119).
Instead of building on that 2018 breakout, Diaz has lost his power-hitting stroke. He has just a 68 OPS+ (32 percent below the MLB average) in 2019, which places him among the five worst-hitting catchers with 200+ PA:
Diaz hasn't been very good against fastballs this season (he's slugging .342 against heat this year, per MLB Statcast), but he wasn't exactly crushing velocity last year either (.385 slugging percentage). The major difference is his performance against breaking and off-speed stuff. In 2018, Diaz crushed five home runs off curveballs and sliders and had a .530 slugging percentage. He ranked 36th in slugging percentage out of 535 MLB hitters who saw 200+ breaking pitches in 2018. He displayed some thump versus off-speed pitches, too, with two homers and a .457 slugging percentage (147th out of 619 big leaguers who saw 100+ offspeed pitches).
In 2019, though, Diaz has gone deep just once on a breaking pitch and has slugged a paltry .259 (344th out of 440 batters with 200+ pitches seen). He has yet to hit a home run against an offspeed pitch and has a .393 slugging percentage (217th among 576 hitters with 50+ pitches seen). In 2018, Diaz put breaking pitches in play at an average of 89 mph. This year, that figure is 85.3 mph. He's also making weaker contact on offspeed stuff (86.8 mph in '18; 84 mph in '19). Diaz has swung and missed a little more often against breaking stuff (35.9 percent whiff rate in 2019, 31.4 percent in 2018), and much more often versus offspeed pitches (31.3 percent in '19, 18.8 percent in '18). In brief, against breaking and offspeed pitches, Diaz is making lousy contact, and less of it.
When you combine Diaz's offensive decline with his continued defensive woes (a topic chronicled in last week's Stats column), you have one of the game's worst catchers this season. Diaz has been worth -1.0 Wins Above Replacement (WAR, which measures a player's offensive, defensive and base running value compared to a waiver-wire caliber talent). That's dead last out of 28 catchers who have 200+ PA this season. Now, the question becomes: What role does Diaz play in 2020 and beyond? Is he still capable of regaining his power swing and being the long-term starter? Or is he, at 28, a backup who had a few great months back in 2018? Considering the lack of catching depth in the Pirates' system, they'd better hope Diaz is capable of more than he has shown so far in 2019.
MORE PIRATES
• Pinch-hit heroes: Pinch hitting is, for a variety of reasons, ridiculously difficult. Batters come off the bench cold, with little more than some batting cage hacks, to face what is typically a fire-breathing reliever with a wipeout secondary pitch. That's why collectively, MLB pinch-hitters have a .726 on-base plus slugging percentage this season, with a park and league-adjusted line that's 8 percent worse than the big league average in all situations. The Pirates, by contrast, have been pinch hit maestros in 2019. With an adjusted batting line that is 49 percent above average, Pittsburgh ranks third in the majors behind only the Red Sox (93 percent above average) and the Twins (55 percent above average). Among Pirates with double-digit pinch-hitting plate appearances, Jose Osuna (190 percent above average), Melky Cabrera (69 percent above average) and Colin Moran (46 percent above average) have been the best.
• Williams hit harder: Entering the 2019 season, Trevor Williams looked like one of the most interesting test cases of the "pitcher, not a thrower" concept. Detractors pointed out that while Williams' 2018 ERA was a sparkling 3.11, his fielding-independent-pitching (FIP) stats suggested his ERA should be closer to 4.50. His proponents fired back by saying that Williams would continue to overachieve thanks to savvy pitch sequencing and the ability to induce weak contact. And indeed, he did limit hard contact last year: opponents put the ball in play at an average of 85.6 mph versus Williams in '18, about 2 mph better than the 87.5 mph big league average. In 2019, Williams' ERA has spiked to 4.96 with component stats that suggest a mid-to-upper fours ERA. And opponents are connecting with more authority this year. Batters have an average exit velocity of 87.5 mph against Williams in 2019. His hard-hit rate (balls put in play at 95+ mph) has spiked from 30.6 percent in '18 to 37.1 percent in '19 (34.4 percent MLB average). The biggest increases have come on Williams' slider (85.2 mph exit velocity in '18, 87.6 mph in '19) and changeup (80.4 mph in '18, 87.6 mph in '19).
PENGUINS
• Jake and Sid connection: For Jake Guentzel, it pays to be on Sidney Crosby's wing. Guentzel nearly doubled his goal total from 2017-18 (22) to 2018-19 (40), and the Penguins were nearly unstoppable when those two skated together this past season. When Guentzel and Crosby were on the same line during five-on-five play, Pittsburgh generated 55.1 percent of total shots, 56.9 percent of scoring chances and 66.7 percent of goals, according to Natural Stat Trick. When Guentzel skated at even strength without Sid, the Penguins had 41.5 percent of total shots, 43.8 percent of scoring chances and 31.6 percent of goals. Guentzel's scoring surge wasn't solely the product of playing with Crosby, but it surely didn't hurt.
• Sid through 31: While the NHL is tracking younger and Crosby is no longer a kid -- top overall NHL draft pick Jack Hughes was five years old when Sid debuted -- the Penguins captain just notched the sixth 100-point season of his career and his first since 2013-14. And, when you adjust for the era in which Crosby has played, you can easily make the case that he's among the best offensive talents we have ever seen through his age-31 season. Hockey Reference tracks a stat called adjusted points, which scales a player's point total to reflect the overall offensive environment at the time that he skated. For example, Crosby has 1,216 actual points during his career, but 1,334 adjusted points (a reflection of how he played during some low-scoring seasons). With those 1,334 adjusted points, Sid trails only Wayne Gretzky (1,850) and Jaromir Jagr (1,403) in adjusted points through age 31. Crosby beat out Mario Lemieux (1,290 adjusted points through age 31), though Mario posted that total in nearly two fewer seasons' worth of games (745, compared to 943 for Crosby).
• Blueger's value: With Matt Cullen officially retiring, Teddy Blueger looks poised to center a bottom six line for the Penguins in 2019-20. He should be an upgrade. Blueger, a 24-year-old Latvian selected in the second round of the 2012 draft, had nearly a point per game with Wilkes-Barre Scranton last season (39 in 45 contests) and then posted 0.36 per game during his first taste of the NHL (Cullen averaged 0.28 in 2018-19). Cullen, though highly respected for his leadership, was one of the game's worst skaters in terms of driving puck possession for his team. With Cullen on the ice during five-on-five play, the Penguins generated -8.2 percent fewer shots compared to when he was on the bench. Blueger was much closer to average (-2.2) at even strength last year, and comes with more offensive upside.
STEELERS
• Tuitt's (de)feats: With a $12 million annual salary on a deal that could keep him with the Steelers through 2022, Stephon Tuitt is paid like an elite defensive end. Some think his production, while good, falls short of that level. Tuitt ranked tied for 29th among defensive ends in sacks last season (5.5), but he ranks higher in some less glorious but still important stats. Tuitt placed 11th among all interior lineman in defeats last season. A Football Outsiders stat, defeats measures when a player makes a tackle for a loss of yardage, a play that results in a turnover, or a tackle or tipped pass that ends a drive. Tuitt had 16 defeats in 2018, one more than linemate Cameron Heyward. He also put pressure on QBs even when he didn't register a sack, collecting 20 QB hits (tied for 11th). Tuitt doesn't compile splashy sack totals, but that's not really his job, either.
• JuJu through two: As JuJu Smith-Schuster gets ready to take over as the Steelers' unquestioned No. 1 receiver, let's take a moment to appreciate just how good he was during his first two NFL seasons as a strong complement -- or sometimes 1A -- to Antonio Brown. Through his first two years, Smith-Schuster ranks fourth in receptions (169), eighth in receiving yards (2,343) and 10th in yards per target (9.6) during the post-merger era (1970-present). He also ranks seventh in catch rate (69 percent) since Pro Football Reference began tracking that metric in 1992. Smith-Schuster still has to prove he's an elite receiver now that he doesn't have a future Hall of Famer lining up on the other side of the field, but we've rarely seen someone dominate like this since draft day.
• Dirty laundry: The Steelers might be seeing yellow, rather than red, as they gather at Saint Vincent College for training camp. In 2018, they committed 111 penalties that cost the team a combined 1,026 yards (third-most in the NFL). They had the most offside penalties in the game (11), according to The Football Database, and ranked third in defensive pass interference (11). Bud Dupree was the Steelers' most penalized player (9), followed by Artie Burns and Vance McDonald (6 apiece). If the Steelers could stop sabotaging themselves, it would go a long way toward returning to the playoffs.
THE NATIONAL TREND
• Senior Circuit dominance: The Pirates have fared very well during interleague play in 2019, boasting a 10-4 record versus the American League. They're hardly alone when it comes to NL clubs beating up on their Junior Circuit brethren. Overall, NL teams have a .561 winning percentage in interleague play this season. That's up from a .527 winning percentage for the NL in 2018, which was the first year that the NL claimed interleague supremacy since 2003. The tide has turned.
