The Colorado Rockies' longest road trip of the season couldn't end quickly enough.

Now, they're heading home with their longest losing streak since last September.

Michael Bourn hit a two-run homer off Adam Ottavino with one out in the ninth inning Sunday, giving the Cleveland Indians a 6-4 victory and a three-game series sweep of Colorado.

The Rockies completed their nine-game, 10-day trip with four straight losses and a 2-7 record. The highest-scoring team in the National League also fell to .500 for the first time since April 20 and is 12-21 overall on the road.

"I wouldn't say happy would describe my mood right now, but I am happy to get the (heck) out of here and get back home," Ottavino said.

Colorado trailed 4-3 heading into the seventh, but tied the game against Indians reliever Bryan Shaw. Brandon Barnes led off with a double and scored three batters later on a sacrifice fly by Charlie Blackmon.

The Rockies also put runners in scoring position in the next two innings, but couldn't push the go-ahead run across the plate.

"We competed really well again, but we didn't do a whole lot of things well," Blackmon said. "When things aren't going your way, that tends to happen a lot. You've just got to put it behind you because in times like these, there is no obvious adjustment to make."

Ottavino (0-2) entered to start the ninth and allowed a leadoff single to Mike Aviles, who advanced to second on a sacrifice bunt by George Kottaras. The right-hander left an 0-1 fastball up in the zone, which Bourn drilled into the right field seats for his first career walk-off homer.

"We were more worried about him pushing the ball through the other side than turning on it," Ottavino said. "He hit it really good, and I obviously didn't expect that."

"In that situation you just look for a pitch to hit, and when you get one to hit you have to make sure you hit it," Bourn said.

Scott Atchison (2-0) struck out the side in the ninth. DJ LeMahieu doubled with two outs, but Blackmon struck out to end the inning.

In the series, Colorado struck out 38 times but remains the hardest NL team to strike out on the year.

Corey Dickerson hit a two-run homer in the second — his career-high seventh of the season — for the Rockies, while Justin Morneau accounted for their third run with an RBI groundout in the third.

Indians right-hander Josh Tomlin allowed three runs in 5 2-3 innings while striking out a career high-tying eight.

"We battled and we came up short, that's the way it went again today," said Colorado manager Walt Weiss, whose team was outscored 46-26 over its nine-game trip.

"We'll get on a plane, go home, and start a winning streak again. Of course, it will be nice to go home, but we need to play well whether we're there or on the road."

Colorado's key hitters struggled during the trip. Carlos Gonzalez reached on a bunt single to start the eighth, but was 2 for 20 in nine games. Troy Tulowitzki broke an 0-for-13 streak with a third-inning single, but ended the trip in a 3-for-23 slump.

Jhoulys Chacin allowed four runs and walked five in five innings, remaining winless on the season. He is 0-5 with a 6.63 ERA in seven starts since his most recent victory on Sept. 20, 2013.

"I put the team in a bad situation," Chacin said. "Especially on this road trip, I have to be better."

NOTES: Rockies 3B Michael Cuddyer, who went 2 for 4 with a run, made his second straight start at the position. Prior to this weekend, he hadn't played the hot corner since 2010 with Minnesota. "I can't believe I've got to do this, just so a 25-year-old (Dickerson) can DH," Cuddyer joked. ... Rockies LHP Rex Brothers tossed a scoreless seventh, but is 0-1 with a 9.82 ERA in his past four appearances. The loss occurred Saturday when he allowed an eighth-inning run in Cleveland's 7-6 victory. ... Colorado has the best home record in the big leagues at 16-7. ... The Rockies have Monday off before beginning a three-game series with Arizona on Tuesday. Colorado LHP Jorge De La Rosa (6-3) takes on Diamondbacks RHP Chase Anderson (3-0) in the opener.