The only other player to accomplish the feat was Bob Nieman of the St. Louis Browns on Sept. 14, 1951. McDonald, 27, also did it in his first career start.
The Cardinals purchased the contract of McDonald, a catcher, from Triple-A Memphis on Sunday and he homered against Cincinnati's Andy Larkin in a pinch-hit appearance on Tuesday.
On Thursday, McDonald hit his second home run on a 1-0 pitch from Osvaldo Fernandez of the Cincinnati Reds into the visitor's bullpen in left to tie the score 3-3.
Manager Tony La Russa talked McDonald out of making a curtain call on Tuesday, reasoning that he didn't want to show up the Reds in a 14-3 blowout victory for St. Louis. This time, teammates Jim Edmonds and Edgar Renteria talked McDonald into waving to the crowd.
McDonald walked in his third career at-bat, in the third inning Thusday.
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