Flowers' drive just inside the foul pole in left field was the third straight hit after Texas right-hander Justin Grimm (2-1) retired 10 in a row on the day he was named AL rookie of the month.
Adrian Beltre's homer in the second was the only hit through five innings against Santiago (1-1), who had six strikeouts and two walks in 5 1-3 innings. The left-hander made his first start of the season and fifth of his career after Peavy was scratched because of back spasms.
RED SOX 3, BLUE JAYS 1
TORONTO (AP) — Ryan Dempster won his second straight start and the Red Sox took advantage of a season-high 10 walks to beat the Blue Jays 3-1.
Dempster (2-2) allowed one run and four hits in six innings. The right-hander, who walked three and struck out four, retired 10 of the final 11 batters he faced.
Winless in his first four starts this season, Dempster posted his first victory by beating Houston a week ago.
Brett Lawrie homered and Colby Rasmus had three hits but the last-place Blue Jays lost for the 12th time in 16 games.
Blue Jays left-hander J.A. Happ (2-2) allowed two runs and three hits in 3 2-3 innings, his shortest start of the season. He matched a career high with seven walks.
TIGERS 7, ASTROS 3, 14 INNINGS
HOUSTON (AP) — Don Kelly had an RBI single to start a four-run 14th inning and the Tigers beat the Astros.
The Tigers tied it in the eighth with help from right-fielder Rick Ankiel's error.
Austin Jackson led off the 14th with a ground-rule double. Jackson advanced to third on a groundout by Torii Hunter before Houston intentionally walked Miguel Cabrera and Prince Fielder to load the bases.
Kelly's dribbling grounder to right field scored Jackson and chased Dallas Keuchel (0-1), who came in to start the 10th.
Matt Tuiasosopo's two-run double made it 6-3 before Detroit added a run on a sacrifice fly by Jhonny Peralta.
Luke Putkonen (1-0), who was called up from Triple-A on Thursday, allowed no hits in the last 2 1-3 innings for the win in a game that took 4 hours, 50 minutes.
ORIOLES 5, ANGELS 1
ANAHEIM, Calif. (AP) — Chris Tillman returned to his hometown and outpitched Joe Blanton with eight scoreless innings of three-hit ball, right fielder Nick Markakis threw out Mike Trout at the plate, and the Orioles beat the Angels in the opener of a four-game series.
Markakis also hit an RBI double and Nate McLouth hit a two-run homer in the ninth.
Tillman (2-1) struck out three, walked two and retired 20 of his last 21 batters.
Albert Pujols homered in the ninth inning against closer Jim Johnson.
Blanton (0-5) allowed three runs — two earned — and eight hits over eight innings.