Tuesday night, J.A. Happ turned in a strong start. The 35-year-old left-hander was faced with a quality Oakland lineup, but gave the Yankees exactly what they needed: an efficient six innings, yielding just two hits and one run. He required only 78 pitches before handing things off to the bullpen in a much-needed road victory.

It was precisely the kind of the start the Yankees have grown accustomed to from Happ. The veteran has been in pinstripes for a matter of weeks, but he has quickly established himself as one of the team’s most dependable starters. Happ is undefeated in seven starts as a Yankee, and owns a 3.10 ERA with the team, striking out more than a batter per inning and walking fewer than two per nine.

What stands out about Happ, beyond simply how well he has performed, is how he has done it. Happ’s pitching strategy flies in the face of the Yankees’ general philosophy, and he has not compromised what makes him successful since coming to the Bronx.

He sticks out like a sore thumb as a fastball-reliant pitcher on a team that relies on the fastball less than any other. The Yankees have made headlines in recent years, dramatically curtailing their use of the heater. Despite possessing the hardest-throwing staff in the league, the Yankees have used fastballs just 46% of the time according to FanGraphs, easily the lowest rate in MLB.

This is no surprise, as the Yankees have been at the bottom of the league in terms of fastball rate for years. They’ve had the lowest fastball rate each of the past three seasons, and we have to go back to 2012 to find the last year in which the Yankees didn’t rank in the bottom three.

Happ is antithetical to that approach. Per FanGraphs, Happ has used his fastball a staggering 73% of the time in 2018, the second-highest rate in the league behind only the ageless Bartolo Colon. He has a higher fastball rate than power pitchers like James Paxton and Justin Verlander, and command artists like Kyle Hendricks and Jose Quintana.

He doesn’t have the pure strength of a Verlander, nor quite the finesse of Hendricks, but Happ uses his fastball-heavy approach with aplomb. Opposing hitters have posted just a .203 average against Happ’s four-seamer, and a .306 wOBA. This is line with his career norms; his batting average against the four-seamer jumped up a bit to .251 last year, but batters posted just a .215 average and .280 wOBA in 2016, and a .237 average and .294 wOBA in 2015.

It’s not precisely clear why Happ is able to handle hitters with his fastball so effectively, though the pitch’s high spin rate probably helps. According to Statcast, Happ’s four-seamer has an average spin rate of 2342, which places him in the 85th percentile among left-handers who have thrown at least 1000 four-seamers. That might help explain the high rate of whiffs and lazy fly balls Happ generates with his heater.

Regardless of exactly why Happ’s fastball is so good, the Yankees have not asked him to stray from his philosophy since joining the team. Courtesy of Baseball Savant, here’s the rate at which Happ has used different pitch types from month to month this season:

There’s hardly been any difference in Happ’s use of fastballs versus breaking and offspeed stuff since coming over to the Yankees. The fact that the Yankees haven’t tinkered with Happ and asked him to deviate bodes well going forward.

Last month, our Joshua Diemert looked into the Yankees’ other starting pitching acquisition, Lance Lynn, and found something similar; Lynn was having success with the Yankees using a steady diet of fastballs. That the Yankees’ two primary pitching imports this season were players with entirely different philosophies than the Yankees themselves, and that the Yanekes didn’t try to force their particular philosophy on them, reflects positively on the club as a whole.

Instead of treating their aversion to fastballs as a one-size-fits-all strategy to be heaved upon any and all acquisitions, the Yankees have exhibited a more nuanced approach here, allowing their added veterans to do what they do best. Maybe either Happ or Lynn could benefit from using more breaking pitches, but even so, the Yankees have clearly not shoved their pitching strategy down their new pitchers’ throats. In doing so, Happ in particular has been able to continue his success in New York. He’s been as reliable as any of the Yankees pitchers, and might be destined to toe the rubber in the playoffs in the Bronx.