DENVER -- Saturday night was set up for Chris Flexen to make a big impression in his Rockies debut.

The right-hander's season started poorly -- a 7.71 ERA in 17 games with the Mariners, followed by a trade to the Mets, followed by being released before he even arrived in Queens. But all of that was in the past.

Instead, he was at Coors Field facing the Athletics in front of a Star Wars Night crowd of greater than 45,000 -- a more sizable audience than one might ordinarily expect for a matchup of teams at the bottom of their league standings. But Flexen gave up six runs (five earned) on four hits, including two homers, while issuing a career-high six walks and a hit batter in 3 2/3 innings of the Rockies' 11-3 defeat.

“I wasn’t nervous at all,” Flexen said. “I was actually pretty excited to pitch in front of this crowd, and pitching for this team. Just one of those where it didn’t work out tonight. I was very inconsistent.”

The Rockies, who have dropped four straight, signed Flexen during the All-Star break out of desperate need. On Saturday, he became their 15th starting pitcher this season, which matches the expansion year of 1993 and 2014 for the club record.

By the time Colorado's post-All-Star break schedule began, four of the team's expected starters were on the injured list, with Germán Márquez and Antonio Senzatela both dealing with season-ending elbow injuries and Ryan Feltner working his way back from a fractured skull. The only one the Rockies were sure to welcome back was lefty Kyle Freeland, who was on the hill for Friday night’s 8-5 loss to Oakland.

After Flexen made two strong starts for Triple-A Albuquerque, the Rockies had every reason to expect better.

“Six walks -- not how you draw it up,” said Rockies manager Bud Black, whose team got the second homer in two nights and the sixth homer in 15 July games from Randal Grichuk -- a player who keeps giving teams reasons to try to trade for him by Tuesday’s deadline. "He’ll be the first to tell you, I’m sure. Six walks will come back to get you.”

The A's scored in the first, with a passed ball from catcher Elias Díaz on Flexen’s first strikeout of Zack Gelof leading to the unearned run after Gelof reached base and scored on Seth Brown's sacrifice fly.

The game unraveled after Flexen walked Jace Peterson and Tyler Soderstrom to open the second. Peterson would score on a wild pitch, and few batters later, Flexen yielded homers to Gelof and Brent Rooker, with a hit-by-pitch absorbed by JJ Bleday in between.

Right fielder Nolan Jones’ juggling catch after hitting the wall to corral Ramón Laureano's fly ball to conclude the frame was the highlight of an inning that kept sinking.

"Inning one was decent, but we dropped one. Inning two was the one that really blew up on me there,” Flexen said. “I had zero feel for the changeup tonight, and I think I threw them maybe cumulatively about 40 feet. Just a tough one."

Flexen had thrown at Coors Field twice before in his career, once as a starter. Denver’s mile-high atmosphere is well known for causing pitchers to have trouble gripping the baseball. But because it's something Colorado pitchers have to adjust to upon donning the home whites, it’s not something they enjoy discussing.

In that respect, Flexen received his initiation as a Rockies pitcher.

“I mean, I’m not going to solely point that out,” Flexen said. “I did struggle getting the feel, but overall I just had a lack of consistency. I threw strikes at times, there were times I’d miss high, try to make an adjustment then overcook it and miss low. It’s one of those days, nothing too specific.”