It was only the second homer as a member of the Angels for Pujols, who came into the game with a .212 batting average. His blast gave the Angels a 4-2 lead and they added a three-run sixth highlighted by a two-run homer from Vernon Wells.
A win Thursday would give the Angels three victories in a row and would equal their longest such streak of the season.
Jerome Williams (4-1) gave up two runs on 10 hits in eight innings for the win. He has been victorious in each of his last four decisions.
Gavin Floyd (3-4) allowed seven runs on 10 hits over six innings to take the loss.
Gordon Beckham and Dayan Viciedo each drove in a run for the White Sox.