DENVER -- Mark Reynolds played in his 1,327th major league game Sunday, and for the first time in his career, Reynolds was mobbed by his jubilant teammates at home plate.

His two-run, two-out homer in the ninth gave the Colorado Rockies a 9-7 win over the Arizona Diamondbacks and a split of a four-game series that was replete with offense and lead changes.

Reynolds' homer was his eighth of the season and the 245th of his career but his first walkoff homer.

"I have almost 250 homers and never had a walkoff," Reynolds said. "I figure I'd run into one every now and then."

Leading off the ninth, Trevor Story, who had tied the game in the seventh with his 19th homer, was hit with a Silvino Bracho (0-1) pitch on the right middle finger. Manager Walt Weiss said Story would not have stayed in the game had it gone to extra innings.

"Everything's OK, just bruised really bad," said Story, adding that X-rays were negative. "It's a little hard to move, just real swollen."

After Story, who reached base five times and scored four runs, was hit with a pitch, Bracho struck out Carlos Gonzalez, whose grand slam had given the Rockies a 6-5 lead in the fifth, and got pinch-hitter Tony Wolters to fly out, before Reynolds drove a 2-1 fastball from Bracho an estimated 464 feet over the wall in center to give the Rockies their first walkoff win of the season.

"I knew he didn't want to walk me and put the guy in scoring position," Reynolds said. "I knew he was going to throw a strike. He threw a fastball for me."

Wolters was the last player on the Rockies bench. And Jason Motte was their lone remaining reliever available.

Carlos Estevez (2-5) pitched the ninth for Colorado, striking out two of the three batters he faced.

Rockies starter Chad Bettis gave up a single and double to start the sixth, followed by a two-run single by Paul Goldschmidt, who had four RBIs. His hard grounder up the middle gave the Diamondbacks a 7-6 lead and knocked both Bettis and second baseman DJ LeMahieu out of the game. LeMahieu deflected the ball with a diving attempt and suffered a left knee contusion.

"I think it'll be fine," said LeMahieu, who will undergo an MRI on Monday. "They think it's just a bruise. It's just sore, just weak."

Bettis allowed a season-high-tying seven runs and a career-high 12 hits, including 10 singles, and was upset he couldn't take less stress off the Rockies' overworked bullpen.

"I knew going into the game that they were hurting a little bit down there (in the bullpen)," Bettis said. "For me, going five innings today was not acceptable."

Yohan Flande, whom the Rockies promoted Saturday from Triple-A Albuquerque, relieved Bettis and got Jake Lamb to ground into a double play. Flande then gave up a single but got Chris Herrmann to ground into an inning-ending double play.

After Jordan Lyles retired the side in order in the seventh, Weiss turned to left-hander Boone Logan in the eighth. He gave up a leadoff single but struck out the next three batters, starting with the dangerous Goldschmidt, whose two-run triple in the fourth had given Arizona a 5-1 lead.

The Diamondbacks finished with 15 hits, giving them a franchise-record 56 hits for a four-game series. The Rockies totaled 52 hits in the series, and the teams combined to score 65 runs -- 35 by the Rockies.

The Diamondbacks scored once in the ninth Thursday to win 7-6 and twice in the ninth Friday to win 10-9 after blowing a five-run lead.

The Rockies watched a 7-1 lead dissolve into a 7-6 advantage Saturday before a four-run eighth gave them an 11-6 win.

And the Rockies overcame a four-run deficit in Sunday's see-saw encounter that saw them go up one run on Gonzalez's fifth career grand slam and fall behind by a run on Goldschmidt's single only to tie the game on Story's homer and finally win it on Reynolds' walkoff shot. The Diamondbacks were trying to go 8-2 on their road trip, which would have been the best 10-game trip in franchise history, but had to settle for 7-3.

"That's just the way things break in this ballpark," Diamondbacks manager Chip Hale said. "You have to live it. We go home tomorrow; we had a real good road trip. I'm happy with the way these guys performed. The effort was relentless."

NOTES: Diamondbacks 1B Paul Goldschmidt extended his on-base streak against the Rockies to a record-tying 48 consecutive games. Mike Piazza also reached base in 48 consecutive games against Colorado. ... The Diamondbacks and Rockies next play Sept. 2 at Coors Field. ... Rockies RF Carlos Gonzalez's grand slam was his 188th home run with the Rockies, tying him with Troy Tulowitzki for fifth all-time in franchise history. ... Rockies SS Trevor Story made his 71st career start and batted fourth for the first time. He has batted first, second, fifth, sixth and seventh this season. ... Diamondbacks SS Nick Ahmed was not in the lineup because of the possibility of having to leave during the game if his wife went into labor. He pinch hit in the seventh and stayed in the game. ... Rockies LHP Jake McGee (sprained left knee) threw his second bullpen session. He's scheduled to do fielding drills Monday and begin a two game rehab assignment Tuesday with Class A Modesto... Rockies RHP Adam Ottavino (ulnar collateral ligament) is scheduled to pitch one inning for Triple-A Albuquerque in his second rehab appearance there after four with Class A Modesto.