Rodriguez matched Gehrig's mark with 23rd slam
Rodriguez hit a full-count pitch from Atlanta's Jonny Venters in the eighth inning into the left field seats to tie the game at 4. It was A-Rod's first slam this season and his 10th homer overall.
Rodriguez ranks fifth on baseball's all-time list with 639 homers. Willie Mays is fourth with 660.
Two batters after Rodriguez tied the game, Nick Swisher connected for a two-run shot to give New York a 6-4 lead.