Mark Teixeira's monster May has been chronicled ad nauseum and it should be. His return to form, along with the return of Alex Rodriguez, led to a significant turnaround for this Yankee team. Since A-Rod's return in Baltimore, Teixeira has hit at a .371 clip with 11 dingers and 29 RBI in just 22 games. Not coincidentally the Yankees are 16-6 in those games and are currently sitting atop the AL East.
Teixeira's return didn't necessarily lead to the Yankees scoring more runs, but it led to the Yankees playing with more confidence offensively. This could be in part why they were able to rally late in numerous May victories.
Teixeira deserves to win a Player of the Month award for May, but will likely fall short to Joe Mauer's absurd month that saw him hit .414 and get on base half the times he came to the plate, not to mention the 11 homers he hit. But this is the Mark Teixeira every Yankee fan was dreaming of when they stole him from the Sox.