By virtue of winning nine straight games and going 13-2 overall in June, the Yankees have overtaken the Rangers for the best record in the American League and are currently looking like the best team in baseball. This week they have a chance to extend that streak when they face two teams they already swept for the first six wins in their streak: the Mets and Braves.
So why are they still No. 5 in these rankings? Because the system encompasses the season as a whole, rather than just the most recent week, and is thus less prone to overreacting to short term spikes. The Yankees are definitely a top tier team, but we should remember that the Rangers looked unbeatable in April as well. The timing of slumps and hot streaks shouldn't cause us to miss the fact that both Texas and New York have now had a stretch of each.
NOTE: All stats are through Sunday, June 10.
Rankings written by the Ben Duronio of Fangraphs. The system used to rank the teams is based not on the current standings or a gut feeling about team quality, but on how well they've performed at the underlying traits that predict future performance better than wins and losses.
wRC+ is an offensive index where 100 is league average and every point above or below that denotes how far from league average a player's performance has been up to that point. It is adjusted for park and league, so it takes into account the context of a player's surroundings, and allows for comparison of performance from players in different situations and in different times.
MLB Power Rankings