Berkman's deal includes a club option for 2014 and is reportedly contingent on the 14-year veteran passing a medical exam.
The six-time all-star played only 32 games last season while battling a torn knee cartilage, hitting .259 with two homers and seven RBI in 81 at-bats for the St. Louis Cardinals.
He helped lead the Cards to a World Series championship the previous season.
Berkman boasts a lifetime average of .296 with 360 home runs and 1,200 RBI in 1,806 games with Houston (1999-2010), the Yankees (2010) and Cardinals (2011-12).
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