SHREVEPORT, La. (AP) _ Gerald Alphin caught four touchdown passes and Winnipeg's defense shut out winless Shreveport in the second half Saturday to earn the Blue Bombers a 38-22 Canadian Football League victory.

Winnipeg's second victory in as many weeks against the Pirates assured the Blue Bombers (10-4) a first-round home game in the playoffs. Shreveport fell to 0-14.

Alphin, a former New Orleans Saint, finished the game with 10 catches for 112 yards. His four touchdowns tied a league game-high for the season.

After Shreveport took a 1-0 lead in the first quarter, Alphin teamed with Keithen McCant for a 25-yard touchdown.

Shreveport answered with a 69-yard touchdown pass from Mike Johnson to Wayne Walker, but the Blue Bombers came back with a 15-yard McCant-to-Alphin touchdown.

Bjorn Nittmo's two field goals tied the score at 14 early in the second, but Alphin's 9-yard touchdown reception put Winnipeg back up.

Shreveport took a 22-21 lead before halftime on Martin Patton's 1-yard touchdown run and a single by Nittmo. However, the Pirates managed only 41 yards after halftime and turned the ball over four times.

The first turnover, a fumbled punt return at the Shreveport 4, led to an 8- yard touchdown catch by Alphin.

Winnipeg kicker Troy Westwood finished the scoring with three field goals, including a 50-yarder, and a single.