Ryan Castellani sat in just about every part of Chase Field while he grew up going to Diamondbacks games as a fan.

He found his favorite spot in the stadium on Monday night: Right on top of the pitcher’s mound.

Castellani threw six strong innings for his first career win, Trevor Story hit his ninth homer of the season and the Colorado Rockies snapped a seven-game losing streak by beating Arizona 3-2.

“You can’t make this stuff up,” Castellani said of returning to Phoenix. “It was an emotional night. It was a lot of fun and I’m glad it worked out. The bullpen made it happen in the end.”

Colorado leadoff hitter Raimel Tapia had three hits and knocked in the go-ahead run with his single in the fifth. He also made a crucial catch against the outfield wall on Kole Calhoun’s long fly ball that ended the seventh and likely saved two runs.

The Diamondbacks have lost six straight and are in last place in the NL West.

MORE: Merrill Kelly scratched from start with shoulder injury in Diamondbacks’ loss to Rockies

Story crushed a solo homer in the first inning that landed well beyond the left-center field wall and gave the Rockies a 1-0 lead.

The 24-year-old Castellani (1-1), who went to high school in Phoenix, gave up three hits over six innings, including two solo homers. He retired seven of the last eight batters he faced and bounced back from a rough outing on Wednesday, when he gave up five runs in a loss against Houston.

“He really knows his strengths,” Rockies catcher Tony Wolters said. “I think he knows how to pitch, how to read hitters and he’s keeping the game simple.”

Daniel Bard continued his impressive comeback story by pitching a scoreless ninth for his second save. The 35-year-old is back in the big leagues for the first time since 2013 and was a mental skills coach for the Diamondbacks coach the past two seasons.

Arizona right-hander Taylor Clarke made his first start of the year after Merrill Kelly was scratched before the game with a right shoulder nerve impingement. The 27-year-old gave up two runs, but just one earned, over four innings.

The Diamondbacks got solo homers from Kole Calhoun and Christian Walker. Walker’s homer down the left-field line came on a hanging breaking ball and tied the game at 2-all in the fourth.

“Offensively, with a couple of solo home runs, you’re looking at two runs and you know a lot of times in this league two runs doesn’t mean you’re going to win a baseball game,” Arizona manager Torey Lovullo said.

Taylor Widener (0-1) took the loss, giving up one run over two innings of relief.

MORE: Arizona Diamondbacks’ Torey Lovullo to ride ‘hot hand’ with struggling bullpen

OFF THE HELMET AND OUT

A strange play happened in the fifth inning when Ketel Marte popped out to shallow left field for the D-backs’ second out. Tapia tried to double Kole Calhoun off first base but the ball skipped past Daniel Murphy.

Calhoun tried to advance to second base but catcher Tony Wolters was backing up the play. He fired the ball to second and it ricocheted off Calhoun’s helmet. Umpires ruled that Calhoun – who appeared to lean into the throw – interfered for the third out.

Lovullo came out to argue and was quickly ejected. It was his second ejection this year and sixth of his D-backs’ career.

TRAINER’S ROOM

Rockies: Wolters took a foul tip off his left leg in the ninth inning and had to leave the game. Drew Butera finished the game in his place. … OF Charlie Blackmon missed the game with a sore quad. Black said he was available to pinch hit.

Diamondbacks: The announcement that Kelly wouldn’t start Monday’s game came about 30 minutes before first pitch. Kelly has been among the D-backs’ most consistent pitchers this season with a 3-2 record and 2.59. Arizona announced the 31-year-old would go on the 10-day injured list.

“I would say the last three or four days it’s kind of taken a turn and just kind of gotten less manageable,” Kelly said. “We’ve been doing a good job of being able to get through days, get through starts or it hasn’t been that bad, but the last couple of days it’s just kind of been building.”

Riley Smith was called up from the team’s alternate site. His first appearance with the D-backs will be his big league debut.

UP NEXT

Rockies: Colorado will start RHP Germán Márquez (2-4, 4.38) on Tuesday.

Diamondbacks: Arizona will counter with LHP Alex Young (1-1, 4.50).