PHILADELPHIA -- The two best pitchers in baseball had a nice, honest chat a couple weekends ago at Citi Field.

“Just in passing we [talk] here and there, making fun of each other’s last start or something like that,” Phillies ace Zack Wheeler said recently about former teammate and Mets ace Jacob deGrom. “And maybe just asking each other a certain tip that they think about at a certain point in their windup or something like that. Just watching him over the years has definitely helped me. We just ask each other questions sometimes, try to help each other out.”

deGrom is one of baseball’s best storylines in 2021 because he is having a historic season. He is 7-2 with a 1.08 ERA, putting him within range of Dutch Leonard’s 0.96 ERA in 1914, which is the lowest single-season ERA by any qualified pitcher since earned runs became official in both leagues in 1913. deGrom is on pace to beat Bob Gibson’s 1.12 ERA in 1968 -- and Dwight Gooden’s 1.53 ERA in 1985, which is the closest anybody has come to Gibson since baseball lowered the mound in 1969.

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It is easy to see why deGrom is an overwhelming favorite to win his third National League Cy Young Award.

Wheeler, who will pitch for the NL in his first All-Star Game on Tuesday, is a heavy favorite to finish second. He is 6-5 with a 2.26 ERA. He leads baseball with 119 2/3 innings. He is second in strikeouts (145) only to deGrom (146).

But is there a path for Wheeler to pull off an upset?

Possibly.

First, before Mets fans get offended at the mere suggestion of it, WAR says deGrom and Wheeler are closer than one might think. FanGraphs ranks deGrom first among all pitchers with a 4.8 WAR, while Wheeler is second (4.5 WAR). Baseball Reference, however, ranks Wheeler slightly ahead of deGrom.

fWAR is based around FIP, which is almost entirely about home runs, strikeouts, walks and hit batsmen -- things pitchers can control. It does not focus on runs because that involves defense, batted-ball luck and more. bWAR starts with runs allowed, then adjusts for opponents, defenses, etc. Wheeler jumps ahead of deGrom in bWAR because the Phillies have the worst defense in baseball and because he has pitched way more innings than deGrom.

Durability and workload are Wheeler’s best and perhaps only shots at an upset.

Wheeler has not missed a turn in the rotation and is averaging 6.65 innings per start. deGrom has missed three starts because of various health issues and is averaging 6.13 innings per start. If Wheeler and deGrom each stay healthy in the second half and each make 16 more starts at their current pace, Wheeler would finish with 226 innings and face 889 batters, while deGrom would finish with 190 innings and face 670 batters.

No starter has pitched more than 223 innings in a season since 2016, while only one starter has won the Cy Young pitching fewer than 190 in a season, not including strike-shortened seasons or 2020: Tampa Bay’s Blake Snell in 2018. He threw 180 2/3.

In an era in which people love to complain about pitchers not going deep into games anymore, things like that could move a Cy Young voter, albeit only if deGrom falls off his historic ERA pace (he has a 3.15 ERA in his last three starts).

It moved this voter in 2016. I had an NL Cy Young vote, and I did not vote for Cubs right-hander Kyle Hendricks, who finished third and led the NL with a 2.13 ERA. Hendricks threw 190 innings compared to Max Scherzer (228 1/3), Madison Bumgarner (226 2/3), Johnny Cueto (219 2/3) and Jon Lester (202 2/3).

Scherzer won that year. He threw 38 1/3 more innings than Hendricks, which is more than an inning of work in every start. He faced 157 more batters, which meant he worked through the lineup a third time far more often. And everybody knows what analytics say about facing a lineup a third time.

Danger.

But if deGrom’s ERA starts to rise in the second half -- say it approaches 2.00 -- while Wheeler’s remains in the low 2’s, but finishes with 36 more innings and faces 219 more batters, maybe Wheeler creeps into the Cy Young conversation. Either way, the Mets and Phillies will be counting on their aces to help them win the NL East. That should be fun enough.