Domingo German leads the Yankees' rotation with a 4.01 ERA in his first full MLB season. (AP)
What a difference a month makes.
At the beginning of August, there were plenty of questions about the Yankees' rotation. Masahiro Tanaka and James Paxton were both scuffling, and Luis Severino had yet to do more than start a throwing program.
While questions still linger, Tanaka and Paxton have led a much-improved rotation into the season's final month while Domingo German has continued his 2019 breakout. Perhaps most important, Severino is in the middle of a Minor League rehab stint and may soon return to the Yankees' rotation, an ace in the hole.
Though the Yankees surely wish Severino was fully stretched out, the timing for the starters' turnaround could hardly be better with the postseason on the horizon. The Yankees' top three of Tanaka, Paxton and German have a 3.43 ERA over their last 21 combined games dating back to July 28. In that time, the Bombers have taken series from the Red Sox, Dodgers and Athletics.
If heading the postseason rotation requires big-game experience, Tanaka gives the Yankees ample exposure in that regard. The right-hander has been New York's best starter in October each of the last two years. In 25 innings, he has a 1.08 ERA and has defeated each of the eventual World Series champions.
As discussed last week, Tanaka has teamed his new-grip splitter with his reliable slider in an adjustment that guided his August success. In his last start against Texas, the right-hander was able to compensate without his best slider, something that wouldn't have been possible without a changed splitter.
Moreover, the Yankees' biggest offseason addition to the rotation provides further reason for optimism. Paxton is undefeated since the start of August and appears to have conquered his confounding first-inning problems. Over two of his last three outings, he struck out 11 Dodgers in a statement victory in Los Angeles and one-hit the Rangers for seven innings with his best stuff of the season.

This is why the Yankees acquired Paxton: to overwhelm opponents and stand near the front of the rotation in October. Even when he was with Seattle, the Canadian native clearly had the pitching acumen to excel against top lineups.
However, it's been German -- not either of the aforementioned veterans -- who has been the Yankees' most consistent starter in 2019. The young right-hander has a 4.01 ERA in 132 1/3 innings, filling in admirably for Severino.
It's worth remembering that this is German's first full season as an MLB starter. He could need more rest down the stretch to excel in October. His midseason IL stint helped alleviate innings-limit concerns, but the team may use its postseason pole position to rest their top pitchers.
German provides an interesting dilemma for the Yankees as he has excelled at home (2.35 ERA in 61 1/3 innings) and had tough outings on the road (5.45 ERA in 71 innings). Two of his best starts, when he outdueled Chris Sale and Clayton Kershaw, did come on the road in recent weeks. Yet the Yankees may want to keep him in the Bronx as much as they can, even if that means pushing Tanaka or Paxton to later in a series.

Beyond Tanaka, Paxton and German, what will the Yankees do with their fourth starter? That role is only needed once per playoff round, though those are three crucial starts. Severino, thus far, is only stretched out to 33 pitches and will resume his rehab with Double-A Trenton this week. Without Spring Training or any MLB innings thus far, Severino is far from a sure bet to re-join the rotation.
CC Sabathia has the veteran experience to be that fourth starter, but his troublesome knee may preclude that option. On the IL for the third time this year, Sabathia has been unable to pitch deep into contests. Even if he were held to one-to-two times through an opposing lineup, he's still faced home run issues in his final season.
J.A. Happ seems unlikely to get a start, though Sabathia's injury could open a role for him, either as a bulk pitcher or long reliever. He has postseason work both in his recent and distant past.
If Severino isn't fully stretched out or the team can only get three-to-four innings from Sabathia and Happ, Chad Green could play a significant role to piggyback the fourth starter. He's worked as an opener often this year and could do that again, On the other hand, he could be an early-game fireman, working two-to-three innings to get the game to the Yankees' top relievers.
The Yankees, of course, need more than just strong starting pitching and will rely upon their super-charged offense and bullpen to carry significant loads. However, the Bombers have the arms to compete in a postseason series and, with Tanaka and Paxton currently at their best, should feel good about how the rotation will hold up against the pressures of October.