DENVER (AP) — Trevor Story tuned up for the All-Star Game with one memorable swing.

Story led off the ninth inning with his 20th homer, and the Colorado Rockies completed a series sweep of the Seattle Mariners with a 4-3 victory on Sunday.

"It was awesome. That's what you dream of, for sure," said Story, a first-time All-Star. "That was my first (game-ending homer) and what a time for it before the break. We took it out on a high note."

Story worked the count to 2-2 against Nick Vincent (3-2) before hitting a drive over the wall in left-center for a dramatic finish to a game played through steady rain.

"I saw a couple pitches, started feeling a little bit more comfortable and that one was just a little more over the plate," Story said.

It was the first career game-ending hit for Story, who tossed his helmet to the ground after rounding third and was showered with ice water and popcorn by his teammates as he stepped on home plate.

Scott Oberg (4-0) got the win with 1 1/3 innings of scoreless relief.

Colorado (51-45) heads into the All-Star break on a roll, winners of five in a row and 10 of 12.

"It's really exciting. Guys are stepping up," All-Star Nolan Arenado said. "We've been playing really good baseball. It's a good feeling. We're going to go into the second half playing really meaningful games, and for a while there it looked like it was getting away from us."

Seattle (58-39) has dropped four straight and seven of nine, but hits the break in second in the AL West behind Houston.

"I'm really proud of our club," Mariners manager Scott Servais said. "We had a really nice first half of the season. These guys continue to compete, all the time. Certainly had the game right there. I thought we had a good chance to win this one today and get off on a bit of a high note.

"We put ourselves in a position by the way we played the first half to gain a good spot here down the stretch in the second half and hopefully get where we ultimately want to go, and that's in the playoffs. This team certainly has enough talent to do that."

The Mariners grabbed a 3-2 lead on Dee Gordon's two-out RBI single off Jake McGee in the seventh. But the Rockies tied it in the bottom half when Ian Desmond tripled and scored on Chris Iannetta's sacrifice fly.

Colorado left-hander Tyler Anderson pitched six innings of five-hit ball, settling down after a slow start.

Seattle opened the game with three straight singles. Mitch Haniger drove in Gordon with a base hit, and Denard Span made it 2-0 with a two-out RBI double.

Colorado rallied in the third, aided by Haniger's error in right. He bobbled Arenado's two-out RBI single, allowing Charlie Blackmon to come home from third with the tying run and Arenado to take second. Mike Leake then fanned Carlos Gonzalez to end the inning.

Leake was charged with an earned run and six hits in six innings.

TOUGH CONDITIONS

The steady rain created slippery conditions on the outfield grass as well as wet, soft footing on the infield dirt. Groundskeepers spread a drying compound on the infield between innings to keep the field playable.

"They made it a lot better than it should have been," Story said. "It was still rough out there but they did a great job."

TRAINER'S ROOM

Rockies: A day after missing a game because of tightness in his lower back, 2B D.J. LeMahieu was back in the starting lineup. "His (pregame) swings were aggressive, no apprehensions," manager Bud Black said. "Mentally he feels good about where he is so he's back out there."

UP NEXT

Mariners: Host the Chicago White Sox on Friday night in their first game after the break.

Rockies: Open a three-game series at Arizona on Friday night.

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