DENVER — The final month of this Phillies season was already ugly. But it turned painful Monday night in a 10-1 blowout loss to the Rockies.

Aaron Altherr left the game with a sprained toe and was examined for a concussion after he slammed into the outfield wall in the fourth inning as he tracked a would-be home run. Zach Eflin was removed with the bases loaded in the third inning after dealing with tightness in his left side. Eflin will fly to Philadelphia on Tuesday for further testing. It seems unlikely that he will make his final start of the season.

Altherr left the field on a cart, which drove him through the left-field gate at Coors Field and away from another brutal loss.

The Phillies have a .500 record for the first time since their 10th game of the season. They were 15 games over .500 on Aug. 5 and have gone 15-30 since. They have lost 16 of their 22 games this month. To salvage a winning record, the Phillies will have to win four of their final six games, all of which come against teams that are playing for postseason stakes. A losing season could be hard to avoid.

"It's not fun," Eflin said. "It is frustrating but at the end of the day, we played some really good baseball this year. A lot of guys have taken a big step forward. We understand that and we're looking forward to being able to have a healthy offseason and have a lot of people make strides in terms of next year. We're excited as ever. In spring training, no one thought we'd be in the position we were a couple weeks ago. We were in the middle of it and we'll just go from there."

Eflin had been dealing with the tightness since he landed awkwardly while fielding a ball on September 14 against Miami. The team was aware of the injury and Eflin used a heating wrap in between innings to find comfort.

"Tonight, it was just a little worse than the last couple starts," Eflin said. "It didn't make any sense to keep going out there for it to get worse heading into the offseason."

The Rockies drove in three runs with the bases loaded in the third inning without a hit. Austin Davis walked in two runs then fired a wild pitch to score another run. The Phillies' lone run came on a homer from Rhys Hoskins in the seventh. By then, the Phillies were down by eight runs, and another painful night was close to being sealed.

"I don't think we're out of gas," Kapler said. "I think we're continuing to fight, we're continuing to battle."

Phillies could use Carlos Santana at third base next season

Carlos Santana had not played an inning at third base in more than four years before he found himself standing there last month. By moving the first baseman across the diamond, manager Gabe Kapler was able to bring Rhys Hoskins in from left field in favor of an optimal defense.

It was a creative move and it has become an almost regular occurrence over the course of the season. Santana started at third Monday night for the 10th time this month. But this switch could have repercussions past September. If the Phillies add a free-agent outfielder – such as Bryce Harper – then moving Hoskins to first base would be a smart move. Would Santana be open to a move to third?

"I don't know," Santana said. "I have no idea what the plan is. The only thing I can control is to play every day and to play hard in whatever position Gabe puts me in."

Santana entered Monday without an error this season at third base. His worst moment came when he bungled a sharp grounder last weekend in Atlanta after the Phillies shifted him near the second-base bag. It was ruled a single.

He has been a top defender at first base for his career and the Phillies would have to hope his athleticism carries over. Santana said playing third base is a bit different. An offseason working there could go a long way.

"I think his performance thus far at third base has been good," Kapler said. "I don't know how predictive that is of what we might get from Carlos at third base moving forward. It's something that we'll sit down with a little bit more perspective and a little less emotion and evaluate when the time is right."

Extra bases

J.P. Crawford, Maikel Franco, Nick Williams, and Jorge Alfaro are all nursing minor injuries and are expected to return this week. …Vince Velasquez will start for the Phillies on Tuesday. The Rockies are expected to use a cast of relievers to piece together the game. … Gabe Kapler said that the starting rotation is still on schedule but that things could change during the final week.

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