Bartolo Colon's age may be catching up to him

Though the Mets’ offense remains more elusive than Sidd Finch, Bartolo Colon returned to form last Wednesday night. After getting blasted for a combined 10 earned runs in 10 innings over two road losses, the 42-year-old shut down the budding Cubs lineup for seven shutout innings. It was fitting for Colon, who has provided a rare break from reality in Flushing this year, offering the occasional age-defying gem on the mound and comic relief in the batter’s box.

But even the most timeless jokes tire after a while, and while Colon looked masterful Wednesday night, he has looked painfully hittable for much of the season. Going into last Wednesday’s start, the righty’s 4.89 ERA and 1.4 HR/9 ranked seventh worst in the National League. Since defeating the punchless Phillies, 3-2, on May 5, Colon had a 6.45 ERA, a .309 batting average against, and an .847 OPS against.

If any story cautions against snap judgments, it’s that of a 285-pound, 42-year-old starting pitcher living on almost nothing but the seventh-slowest fastball in baseball. From 2006 to 2009, Colon failed to reach 100 innings in any season and compiled a 5.18 ERA. In 2010, he was out of baseball at age 37. Yet three years later, a 40-year-old Colon finished sixth in AL Cy Young voting, having compiled 18 wins and a 2.65 ERA.

Indeed, a quick scan of traditional barometers suggests Colon’s struggles may be a matter of luck. He has had the best command in baseball this season. After setting a Mets record with 48.1 consecutive innings pitched without a walk, Colon entered Wednesday with a league-leading 1.0 BB/9. As Eno Sarris of Fangraphs points out, strikeouts minus walks is the best in-season predictor of ERA, and Colon ranks 29th out of 98 qualified major league starters in that measure. For context, that’s two spots behind the Cardinals’ Carlos Martinez and three ahead of Colon’s opponent last week, Jon Lester. All measures that attempt to filter luck and fielding out of a pitcher’s earned run average—SIERA, xFIP, FIP—pin Colon between 3.70 and 3.89; no ace, but more than reasonable for a team’s sixth-best starter.

Still, Sarris suggests that Colon may not be due for a resurgence, citing the veteran’s limited velocity:

"What about Mike Fiers and Bartolo Colon? They’ve both had homer issues in the past, and their fastballs don’t crack 90 on average. For a while, Ted Lilly had great K-BB% and yet gave up all those homers and had ERAs in the high threes…Bartolo Colon, Matt Shoemaker, Phil Hughes, and Mike Fiers? Look at their arsenals. They’re going to give up homers, and it may not get better as the weather warms."

Colon’s velocity has dropped off in recent seasons, falling from an average of 90.2 mph with the A’s in 2012 to 88.4 mph this season. Fangraphs’ Jeff Zimmerman showed in May that as velocity decreases, home run rates and home run per fly ball rates (HR/FB) go up.

After the Yankees signed Colon following his 2010 hiatus, his true resurgence as a frontline starter came in Oakland. The Coliseum was one of the best pitcher’s parks in baseball in 2011 to 2012, and from there Colon came to the even-more-spacious Citi Field. But the Mets moved the fences in again during the offseason, and Citi Field has become a hitter’s park for the first time in its history. Combine that with Colon’s diminishing velocity, and you have a situation that almost ensures that the bleachers will get peppered. Although most starters maintain a HR/FB ratio of around 9.5%, Colon’s sits at 11.9% and that’s not likely to come down.

It’s not just age or the outfield walls that have caught up with Colon; it’s also major league hitters. For the last 10 years or so, conventional wisdom dictated that hitters should be patient early in order to drive up pitch counts and force teams to use their middle relievers. But now, as ESPN’s Buster Olney noted in April, middle relief is far more intimidating, with many teams sporting six or seven relievers who can touch the mid-90s. As a result, previously patient hitters like Mike Trout and Matt Carpenter are getting aggressive.

The difference seems negligible; hitters are seeing an average of 3.79 pitches per plate appearance this season, down from 3.83 in 2014. But that continues a decline that began in 2013 and is the lowest it’s been since 2007. The numbers on first-pitch aggression are even more profound: major league hitters are swinging at 28.8% of first pitches this year, the highest such rate since 2002.

As a starter who relies on attacking the zone and getting ahead, Colon has probably been hit harder (pun intended) than any major league starter by this new offensive approach. The righty has thrown a higher percentage of pitches in the zone this season than any National League starter, and more first-pitch strikes than all but three. Hitters are taking note, swinging at the first pitch just under 30% of the time against Colon—the highest rate he’s seen since returning to baseball—and raking .333 with a .905 OPS on those pitches.

Evidently, no one gave the Cubs the memo. No Chicago batter swung at the first pitch until Jonathan Herrera did with two outs in the fifth inning. During the third time through the order, the Cubs got more aggressive. Although they came up empty, other teams have burned Colon in the second and third times through the order: Colon entered Wednesday’s game with an 8.50 ERA in the fourth inning and a 6.50 mark in the fifth, and opponents are hitting .312 with a .918 OPS the third time through the order. As more teams take note of this as the season goes on, Colon could find himself in trouble.

The news on the batted-ball front isn’t all bad, though. Colon’s ground ball and fly ball rates are right in line with his averages from recent years, and he’s actually allowing a greater percentage of softly hit balls than he did in 2014. Looking at pitchers over 40 who threw at least 100 innings since 2002—the first year for which Fangraphs has strike percentage data —we see four pitchers who succeeded while living in the strike zone as often as Colon does. Those four are Randy Johnson, Greg Maddux, Curt Schilling, and Terry Mulholland. All but Mulholland were about league-average or better. It’s a terribly small sample size, though, and none of those pitchers relied nearly as heavily on their fastballs as Colon does.

More telling from the data set of starters over 40 years old is that most of them were very good until becoming very bad very quickly. The Giants’ Jeff Fassero’s ERA jumped from 4.05 ERA to 7.08 in his last year, David Wells’s from 4.42 to 5.43, Randy Johnson’s from 3.91 to 4.88, and Kenny Rogers’s from 4.43 to 5.70. Jamie Moyer and Tom Glavine similarly experienced sudden spikes in ERA, followed shortly thereafter by exits from Major League Baseball. There’s some obvious selection bias there, but the lesson still holds: old pitchers can fall off fast.

Bartolo Colon has not been the same pitcher since the second half of last year. Entering Wednesday’s start, he sported a 4.60 ERA and an opponents’ batting average of .285 over the last 365 days. Colon proved on Wednesday that he hasn’t reached the station, but he might be running low on gas. We'll see how he fares tonight against the World Champion Giants.