Cook was struck in the lower right leg by a line drive off the bat of Joey Votto in the sixth inning. The right-hander hobbled around the mound for a few minutes, before gingerly walking off the field and into the dugout. The team reported the injury as a bruise, but X-rays revealed it was more serious.
Cook (6-8) allowed one run and six hits in five-plus innings.
Tulowitzki provided the bulk of the offense, hitting a three-run homer off Bronson Arroyo (14-10) in the third and a solo shot two innings later.
The Rockies matched their longest winning streak of the season and remained 4 1/2 games behind the Atlanta Braves in the NL wild-card race.
Padres 4 Dodgers 0: In San Diego, rookie Cory Luebke struck out seven in six sparkling innings, Luis Durango hit a key two-run single and the Padres added to their lead in the NL West.
San Diego has won three consecutive games since losing 10 in a row and is two ahead of San Francisco after the Giants lost 3-1 at Arizona. The Padres will host the Giants in an important four-game series beginning Thursday.
Luebke (1-1) gave San Diego a big lift in his second major league start, holding the Dodgers to two hits.
Four relievers combined to finish the three-hitter. Luke Gregerson got five outs for his second save in seven opportunities.
Diamondbacks 3 Giants 1: In Phoenix, Daniel Hudson pitched seven effective innings and Arizona snapped San Francisco’s four-game winning streak.
Miguel Montero , Stephen Drew and Kelly Johnson each drove in a run for Arizona, which ended a four-game skid. Hudson (5-1) settled down after Freddy Sanchez’s first-inning homer, allowing just four more hits.
Barry Zito (8-12) was almost as good as Hudson, working six solid innings, but it wasn’t enough for San Francisco.
Phillies 10 Marlins 6: In Philadelphia, Ryan Howard had six RBIs and Philadelphia backed Cole Hamels with a rare burst of the run support he had been missing most of the season.
Howard hit his 28th homer of the season and the NL East-leading Phillies had a season-high 18 hits.
Hamels (10-10) tossed four-hit ball over seven innings and extended his consecutive scoreless innings streak to 25. He struck out five and won his third straight start.
Braves 9 Pirates 3: In Pittsburgh, Omar Infante had three hits, Derek Lowe beat Pittsburgh for the 10th straight time and Atlanta got the breakout victory it badly needed.
The Braves opened leads of 3-0 in the first and 8-0 in the third after being held to two runs or fewer in five of their previous six games.
Brewers 8 Cardinals 1: In Milwaukee, Ryan Braun hit a three-run homer and Milwaukee roughed up St. Louis rookie Jaime Garcia .
Albert Pujols hit his 36th homer in the first for the Cardinals, but that was the only run Chris Capuano (3-3) allowed over seven innings.
Garcia (13-7) had been looking for his fourth straight win. Instead, he gave up a career-high seven runs as his ERA rose to 2.69.
Astros 4 Cubs 0: In Chicago, Brett Myers struck out eight in seven crisp innings and Hunter Pence homered, leading Houston to the victory.
Myers (11-7) allowed three hits and walked one, improving to 10-3 with a 2.21 ERA in 17 career games against the Cubs. The right-hander is 3-0 with a 1.76 ERA in his last six starts overall.
Mets 3 Nationals 2: In Washington, pinch-hitter Nick Evans delivered a tiebreaking double in the seventh inning, rewarding R.A. Dickey for an effective start and helping the Mets get the victory.
Josh Thole led off the Mets seventh with a walk against Livan Hernandez (9-11) and moved to second on Ruben Tejada’s sacrifice. After Lucas Duda was announced as a pinch hitter, Sean Burnett relieved and the Mets countered with Evans, who grounded a broken-bat double past the reach of first baseman Adam Dunn to make it 3-2.
