SAN FRANCISCO -- Tyler Beede had been hoping to end his rookie season on a high note, and he appeared well on his way to accomplishing that goal before a left oblique injury forced him to depart after only 3 1/3 innings in the Giants’ 8-3 win over the Rockies on Thursday at Oracle Park.

Beede did not allow a hit over his first three innings, but he appeared to tweak his left side in the fourth after blowing a 95 mph fastball past Ryan McMahon for his seventh strikeout of the afternoon. Beede immediately grabbed his side, receiving medical attention from team athletic trainer Dave Groeschner before exiting the game. He was sent for an MRI exam following the game to assess the severity of the injury.

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It was an unfortunate ending considering the stuff Beede had been flashing against Colorado. He averaged 95 mph on his fastball and topped out at 97 mph, mixing in a sharp curveball that induced six swinging strikes. The only runner to reach base against the 26-year-old right-hander was Yonathan Daza, who struck out to start the third but reached first base after Beede’s curveball skipped away from catcher Aramis Garcia for a wild pitch.

“It’s too bad,” manager Bruce Bochy said. “Really, what a bad break. That’s as good as stuff as he’s thrown all year. He was really locked in with all his pitches.”

Beede concluded his rookie campaign with a 5.08 ERA over 117 innings for the Giants, who stuck with the former first-round Draft pick even as he encountered his share of adversity in his bid to establish himself as a reliable Major League starter this season.

The pieces appeared to come together for Beede after he fired eight shutout innings against the Mets on July 19, but he then spiraled into a deep second-half funk that saw him go 0-6 with a 7.05 ERA over his next eight outings. But after rectifying his command issues, Beede rebounded to post a 2.61 ERA over his final four starts of the season.

“It’s been an up-and-down year, no question,” Bochy said. “No getting around that with him, but you look at his last few starts, they’ve definitely been better. He has shown a ton of improvement, I think. That’s what it’s about. As I’ve said so many times, you’re going to have growing pains with these guys. But you look at the equipment he has, he’s got the ability to be a quality starter up here. I think he should feel good about where he’s at right now.”

Despite his inconsistent results, the Giants recognize that Beede has the repertoire to develop into an impact arm, which should put him squarely in the mix for a spot in the club’s starting rotation next year.

“He got put in a lot of situations that I’m not so sure he’s been in before and he figured out a way to dig down deep in some really big starts for us,” said Mike Yastrzemski, who played with Beede at Vanderbilt. “I haven’t heard about how he’s doing yet, but hopefully he’s going to be fine and nothing serious is done. Watching him throw that well in his last outing was promising.”

A peek ahead to 2020

The Giants received key offensive contributions Thursday from two rookies who have the potential to become significant pieces of their 2020 lineup. Yastrzemski and second baseman Mauricio Dubon each homered and doubled, combining to go 5-for-7 with three RBIs against the Rockies.

“I take pleasure watching guys come up and do well,” Bochy said. “You pull for them. You want them to do well and show what they’re capable of doing and watch their development.”

Dubόn has already drawn rave reviews from the Giants for his game awareness and instincts on defense, but he’s also showing that he has the ability to impact the game offensively. The 25-year-old batted leadoff and crushed his fourth home run of the season in the seventh, launching an inside slider from reliever Sam Howard to left field to extend the Giants’ lead to 4-2. He’s hitting .286 with a .796 OPS over 25 games with San Francisco.

“I’m trying to get better every day,” Dubόn said. “There’s room for improvement, and I just want to keep getting better.”

Acquired from the Brewers in exchange for Drew Pomeranz and Ray Black at the Trade Deadline, Dubόn’s performance this month should make him a solid bet to be part of the Giants’ Opening Day infield next year.

Yastrzemski, meanwhile, came off the bench to crush his 21st home run of the season in the fourth, a 429-foot shot to the deepest part of the ballpark. After toiling in the Minors for seven seasons, Yastrzemski is now tied with Kevin Pillar for the team lead in home runs, a remarkable feat considering Yastrzemski didn’t debut with San Francisco until May 25.

“Looking back on it, it’s a moment that I waited for for a long time and really worked hard to get to,” the 29-year-old Yastrzemski said. “I’m kind of remembering the process that it took and not taking it for granted.”