The Yankees have gone 15-12 since July 1. That’s not bad at all, considering that record amounts to a 90-win pace over 162 games. However, that record does look worse than it could have been, considering that the majority of the games they played during that stretch were against the likes of the Blue Jays, Mets, Royals, and Orioles. It doesn’t help that the Red Sox have been red hot over the same period, stretching their division lead over the Yankees from zero games on July 1 to 7.5 games on August 3. While Boston has emerged as the favorite for the division, the Yankees have more or less spun their wheels.

Several factors stick out as root causes of the Yankees’ recent struggles. Some blame the Yankees’ lackluster performance against the lesser teams in the AL East, which has certainly been frustrating to watch. Others point to poor fundamentals, which I would normally tend to eyeroll at, but were certainly on display during Thursday’s 15-7 loss at the hands of the Red Sox.

Looking at the bigger picture, however, the problem with the Yankees becomes clear, and in some ways it’s been clear all along. More often than not, it’s been the starting pitching, considered the Yankees’ weakest link even prior to the season, that has hamstrung the Yankees in their most recent stretch.

It’s easy to single out the Yankees’ starting pitching, because their poor performance literally sticks out like a poor thumb. Regarding the offense, consider this: the Yankees have failed to score more than five runs only seven times since July 1. For reference, last year teams that scored more than five runs won 62% of their games. That means in 20 out of 27 games the Yankees’ offense has scored enough runs to give the team a strong chance to win. Whatever is ailing the Yankees, it ain’t the offense.

The relief group isn’t entirely to blame, either. While the bullpen’s 4.38 ERA over the past 30 days is unbecoming of their reputation, that mark is inflated by a high .322 BABIP and a low-ish 72.4% LOB, both very fluky statistics. By FIP- as well as fWAR, the Yankees’ relievers rank 7th out of all MLB over the same stretch. While the Yankees’ bullpen hasn’t been as shutdown as we’d like, they’re still comfortably above average by most pitching measures.

No, what’s torpedoed the Yankees’ division chances is their starting pitching. Over the past 30 days, Yankee starters have posted an ERA of 4.97 and a FIP of 4.95, good for 0.8 fWAR (22nd in MLB). They’ve also only given the team 121.1 innings over 24 starts, good for eighth-fewest in the majors. In terms of both quality and quantity, the Yankees’ starting pitching has left a lot to be desired over the past month.

I imagine that many fan, upon perusing that last paragraph, immediately went “well yeah, because of Sonny Gray”. They would be half right, as Gray has indeed pitched poorly over the past month, posting an ERA of 6.00 over five starts. However, by ERA, Luis Severino has been even worse, posting a 8.84 mark over four starts.

CC Sabathia hasn’t been much better, running 5.55 ERA over five starts. Excluding the recently joined J.A. Happ, who gave the Yankees a quality start in his only appearance for them to date, the only Yankees starters who have posted an ERA below 5 over the past month have been Masahiro Tanaka and - you guessed it - Luis Cessa.

Asking the offense and the bullpen to compensate for that kind of overall performance is a bit too much. However, that is precisely how these Yankees were built: in lieu of a strong starting rotation, Brian Cashman assembled one of the best lineups in the AL to out-slug opponents, along with a terrifying bullpen to hand games over to if and when the starters fell short. The formula itself isn’t a bad one, it just needs a certain level of starting pitching to be sustainable. It’s just that the recent performance by the Yankees’ staff hasn’t met that threshold.

It’s easy to say, with hindsight, that Cashman should have tried to bolster the rotation prior to the season. However, there’s plenty of evidence that he did, going after Shohei Ohtani and Gerrit Cole in the offseason. Those deals just never materialized, and the other options were frankly not all that appealing.

Cashman built the team he could with the cards he was dealt. It’s important to remember that the roster he constructed has worked out for the most part, as they find themselves at the start of August nearly 30 games above .500. What happens next largely depends on how the rotation can bounce back after a rough past month. They never said it was going to be easy.

All stats courtesy of FanGraphs.com and Baseball-Reference.com.