The New York Yankees have won 13 games in a row. Their winning streak came to an end on Saturday, falling to the Oakland A’s 3-2. The Yankees are a new team since the trade deadline. Before the July 31 deadline, the Yankees were hovering around .500, sat lazily in third place, and were not in playoff contention. Radio hosts, the New York Media, and Yankees fans were calling for the sacrifice of GM Brian Cashman and Aaron Boone. But Hal Steinbrenner stood by his management and blamed the players for the Yankees’ 2021 season failures. At the time, only three weeks before the trade deadline, everyone thought this was a curious choice. This roster was ostensibly bad. But it was one Cashman created, so was one that only Cashman could fix.

And fix it he did.

Only three weeks later, Cashman made trades to acquire two left-handed bats in Joey Gallo and Anthony Rizzo. And while Gallo was not an immediate performer, Rizzo burst onto the scene, becoming the first Yankee to have six RBI in six games. Since the trade deadline, the Yankees have surged past the Red Sox and currently hold the top Wild Card spot for the playoffs. These are not your Spring Training Yankees. But the question remains: is this sustainable? Are the Yankees this good?

Going into the 2021 season, many pundits picked them to possess the best record in the American League, nearing 100 wins. Currently, FanGraphs is confident the Yankees will make the playoffs, sitting at a 96% chance to make the playoffs, and a 10% chance to win the World Series. 

But could the difference between a .500 ball club and a one that goes on double-digit winning streaks really be just the addition of two left-handed hitters? Maybe.

Before the acquisitions of Gallo and Rizzo, the Yankees had one left-handed starter in their lineup, Rougned Odor. And, as most baseball fans know, Odor fits perfectly in line with the pre-trade deadline Yankees’ MO: strikeout or home run, there is no in-between. But, by adding Rizzo and Gallo, the latter being similar to Odor, it lengthened their lineup. Before the deadline, the Yankees’ slash line was .234/.324/.393, now, during their winning streak, they scored an average of 5.7 runs a game, and slashed .256/.345/.495. 

This is a tale of two Yankees, both performing against expectations. During the Yankees’ winning streak, their pitching was also elite. The Yankees had the best ERA in the American League in August, at 3.31, and the second-best strikeout rate in the American League, nearing 25%. Aside from Gerritt Cole, this was not anticipated. The remainder of the Yankees rotation consists of Jameson Taillon, Jordan Montgomery, and Andrew Heaney. The lowest career ERA of those, is Taillon, with a 3.78 career ERA. The recent stretch of dominant pitching is likely a result of their schedule, having played the Minnesota Twins and the--at the time struggling--Boston Red Sox. 

But the Yankees weren’t built around pitching, instead, they were built to bludgeon the ball. And they have been. But, as seen so often, this offense is streaky. Stanton is a prime example of this. Currently, he is on a hot stretch slashing .324/.417/.663. In July, it was the mirror opposite, where he slashed .214/.320/.333 with 31 strikeouts. So, while everyone is excited by the Yankees’ recent stretch of dominance, a closer look suggests it is not sustainable. Not to mention, they continue to stay behind the Rays for first place in the AL East, since the Rays, the reigning AL Champs, show no signs of streaks, and maintain a 5 game lead in the AL East.

So the Yankees’ main concern will be can they continue this hot streak, or something similar, and, more than likely, which Yankee team shows up in that one-game Wild Card playoff? Because while this August stretch has been historic, the Yankees were a questionable team for the majority of the season. Those concerns usually return. So stay tuned. September baseball is always a treat.