The Detroit Tigers opened their weekend series with the Colorado Rockies with a 4-2 win Friday night at Comerica Park. Detroit (59-47) took a 3-0 lead in the fifth inning on the strength of a Rajai Davis 2-run single and an RBI double from Ian Kinsler. The Rockies (44-65) closed the gap to one with two runs in the top of the seventh but could get no closer.  Victor Martinez completed the scoring in the bottom of the inning with his RBI single. Justin Verlander (10-9) went eight innings with five strikeouts for the win and Joe Nathan pitched a perfect ninth for his 22nd save. Franklin Morales (5-6) took the loss.  The two teams go at it again Saturday night with Rick Porcello (12-5) throwing for the Tigers while Tyler Matzek (2-5) goes for Colorado. Pregame coverage beings at 6:40pm on Lansing's Big Talker 1240 WJIM.