The biggest hurdle standing in the way of the New York Mets making the playoff this year is their bullpen. It is the same problem that has persisted all season, as Seth Lugo has consistently been the only reliable arm the Mets can turn to.

While Justin Wilson and Luis Avilan have been good as of late, Jeurys Familia and Edwin Diaz continue to falter, putting Mickey Callaway in a position where it feels like he is playing Russian roulette when trying to get outs from his pen.

When it comes to Diaz, his season has truly been baffling to try to understand. This was the best closer in baseball last year. Someone so dominant that the Mets traded two of their best prospects, while taking on a massive long-term contract in Robinson Cano to acquire. Yet here he sits with a 5.65 ERA, six blown saves and a 1-7 record on the season.

The strikeout numbers have still been great, as Diaz has 86 punchouts in 51 innings pitched. But every time you think Diaz is turning the corner, he has another meltdown like the one from Tuesday night, allowing a double and a home run that sealed the Mets fate in a seven-run ninth inning for the Washington Nationals.

So is there any explanation that can be found from Diaz’s nightmare of a season?

Well there just might be one. The guy has been terrible whenever pitching on consecutive days.

Diaz sports a 15.00 ERA in games pitched on no days rest. He has also given up eight of his career-high 13 home runs in those affairs. Diaz features his worst strikeout to walk ratio (2.50), opposing batter’s OPS (1.558) and batting average against (.432) when pitching without any rest. Diaz has faced 51 batters in those situations and has given up 19 hits, 12 of which for extra-bases, while also yielding 15 runs.

Compare those numbers to his 1.93 ERA in games pitching on one days rest and it becomes clear that Callaway needs to avoid going to Diaz on back-to-back days. For whatever it’s worth, Diaz has not been great when pitching on two days rest either. He has a 6.17 ERA in 13 games pitched in those situations.

So while it is hard to work around such great limitations, with such a small margin of error in this Wild Card race, the Mets can’t afford to ignore these trends. It would make sense for New York to pitch Diaz every other day, regardless of the game situation, just to bring some consistency to his routine. The 1.93 ERA that he has accumulated on one days rest is across 17 games and 14 innings pitched, his largest sample size when it comes to days rest.

If they can keep Diaz on this schedule, maybe he will prove an asset rather than a detriment over the last 23 games of the season. Even if Callaway doesn’t follow such a plan by the book, one thing is clear. Diaz should not pitch two days in a row for the remainder of this season.