For long stretches in each of the last two seasons, Zack Wheeler was every bit as effective as Aaron Nola.
Wheeler had four terrific months in 2018, posting a 2.52 ERA over his final 20 starts beginning on June 1.
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In 2019, he found his groove right around midseason, pitching to a 3.04 ERA over his final 16 starts.
When you hear the phrase "untapped potential" in relation to Wheeler, this is what it means. It means that if he can pitch like this a bit more consistently - four good months instead of two - he can be a legitimate ace.
If he can't? Well then, if you trust his stuff and his results the last two years, you're getting no worse than a low-end No. 2 starter. Wheeler has made 60 starts the last two seasons with a 3.65 ERA, 1.19 WHIP, a strikeout per inning and less than a home run per nine.
Those numbers might not jump off the page, but they are impressive when you consider the surge in home runs in 2019 and especially so when considering his workload.
Wheeler is one of only 12 pitchers to reach 375 combined innings the last two seasons. The others are Jacob deGrom, Justin Verlander, Gerrit Cole, Max Scherzer, Zack Greinke, Aaron Nola, Patrick Corbin, Trevor Bauer, Jose Berrios, Miles Mikolas and Mike Leake.
In 2019, Wheeler made 18 quality starts (at least six innings with three earned runs or fewer). Nola also made 18. Zach Eflin had 14, Jake Arrieta had 10 and no other Phillie was in double-digits.
When Nola did not start a game for the Phillies in 2019, they received a quality start 31 percent of the time - less than once every three games.
Wheeler obviously helps with that. Think back to late last season when the Phillies could generate no momentum and had such a smaller chance to win when anyone was on the mound other than their ace. Wheeler changes that. He offers more of a chance for series wins, sweeps, actual winning streaks.
He also brings velocity, something the Phillies' rotation has sorely lacked for years. Wheeler's four-seam fastball averaged a career-best 96.7 mph last season, fourth-fastest in the majors behind Noah Syndergaard, Cole and deGrom.
The Phillies have never had a starting pitcher throw at least 100 innings in a season and average better than 95 mph with his fastball. Nick Pivetta and Vince Velasquez came the closest. Wheeler has done it comfortably in back-to-back seasons.
Velocity is not the only thing, especially these days when so many have it, but it is obviously still a major part of missing bats and getting outs. Because Wheeler has 3 or 4 mph more on his fastball than Nola, and because he can locate significantly better than Pivetta or Velasquez, he offers the Phillies' rotation a different, much-needed look.
This is not to say Wheeler comes without flaws or concerns. He hasn't yet ripped off a string of strong seasons. Two is a start and the Phillies are banking on it continuing.
He hasn't been a Top 10 Cy Young finisher, though he should have been in '18.
He's never reached 200 innings in a season, though some of that was because of caution the Mets exercised with him.
And Wheeler, despite the velo, has gone through plenty of multi-start stretches where he's been hit hard and doesn't miss many bats, in a way you don't see with the tippy-top guys like Scherzer and deGrom (which Wheeler is not).
He had three starts in a row like that last August and two straight in June.
But Wheeler is as capable of 7 innings, 1 run, 11 strikeouts as any pitcher in either league. When he's on, he can be so, so good. He went at least seven innings 15 times last season and allowed one or no runs in seven of them.
This one addition will not boost the Phillies to 90 wins, but it's the first giant step to another critical offseason.
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