Walker Buehler, who struck out 11 of 12 batters with six strikeouts from the second through fifth innings on Saturday night, could play in the postseason rotation for the Dodgers.

The Buehler who allowed three runs and three hits, walked one batter and hit another while throwing 42 pitches in the first two up-and-down innings? Not so much.

The start-to-finish consistency and extended periods of dominance that made Buehler the team’s ace from 2019-2021 continued to elude the right-hander in a 6-3 loss to the Colorado Rockies in front of 52,267 sold-out fans at Chavez Ravine, further clouding the team’s chances of playoff pitching.

Buehler, who missed the first five weeks of the season because of his second Tommy John surgery and two months from mid-June to mid-August because of a left hip injury, allowed four earned runs and five hits in 5.5 innings, while allowing nine strikeouts and a walk, falling to 1-6 with a 5.63 earned run average in 13 starts.

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Saturday night’s inconsistent performance somewhat undid the progress Buehler made in his last start, when he battled through early control issues to yield two runs (one earned) and five strikeouts in a six-inning outing in a 9-2 win at Atlanta on Sept. 15.

“I’ve had some rough patches where I really doubted if I had what it took to compete,” Buehler said. “Tonight I felt like I could compete, but I just didn’t make the big shots in the big situations or I made little mistakes in the big situations, and that’s frustrating. … There were some encouraging things in there, but obviously not good enough at this point in the year when we’re trying to keep the lead in the division.”

The loss reduced the Dodgers’ lead in the National League West to three games over San Diego and five over Arizona, leaving their magic number to win the division at five games with seven games remaining, three of which are at home against the Padres this week.

Buehler put the Dodgers behind early by continuing his pattern of struggles in the first innings followed by three or four innings of effectiveness.

“He puts pressure on himself in the first inning,” manager Dave Roberts said. “We have to find a way to get that clean first inning because it looks like he’s finding his rhythm in the third, fourth and fifth innings.”

Roberts actually saw more reasons for optimism than concern, pointing to the 14 swinging strikes Buehler threw, five with his fastball and four with his curveball.

With injuries plaguing the rotation, Roberts may have no choice but to rely on Buehler in October, but the manager seems to have no qualms about giving Buehler the ball for a playoff start.

“I’ve never been more confident in Walker this year,” Roberts said. “I think he was in the mix, but obviously he’d have to be successful to believe that. I think with nine strikeouts and his command of the baseball, I’m very confident he’ll start in a playoff game for us.”

Buehler allowed one run in a 27-pitch first inning that included Charlie Blackmon’s leadoff double, Ezequiel Tovar’s walk and Michael Toglia’s RBI fielder’s choice. Buehler minimized the damage by striking out Brendan Rodgers and Sam Hilliard with 92-mph cut fastballs while runners were on second and third base.

The Rockies extended their lead to 3-0 in the second when Nolan Jones got to first base with an infield single, Jacob Stallings was hit by a pitch and Tovar hit a two-out, two-run double into the left field corner.

The Dodgers cut the deficit to 3-2 in the third inning when Shohei Ohtani walked and Mookie Betts hit a 93-mph sinker from right-hander Cal Quantrill into left-center with the first pitch for his 18th home run.

Max Muncy walked with one out in the fourth inning, Gavin Lux hit a single to right and rookie catcher Hunter Feduccia hit a single to right for his first RBI and a 3-3 tie.

Buehler recovered from his rocky start, striking out nine straight batters before hitting a 77-mile-per-hour curveball on the first pitch to Ryan McMahon, who hit a home run – his 20th of the season – into the left-center field with two outs to give Colorado a 4-3 lead in the fifth inning.

“We tied the game and then I allowed the home run — that was really disheartening,” Buehler said. “The number of misses was encouraging, but at the end of the day, none of that really matters if they keep putting up good numbers.”

The Dodgers posed a threat in the fifth inning by loading the bases with two outs, but Rockies left-hander Luis Peralta replaced Quantrill and struck out left-handed hitter Lux with a 97-mph fastball, ending the inning.

The Rockies scored two key extra runs in the ninth inning against Daniel Hudson: Jake Cave hit a double to right with one out and Blackmon hit a 95 mph, 0-and-2 fastball for a two-run homer to right for a 6-3 lead.

The Dodgers positioned themselves for a dramatic comeback victory when they loaded the bases with two outs in the ninth inning – with Ohtani stealing his 53rd base – but Rockies right-hander Seth Halvorsen blew off a 100-mph fastball from Muncy for a game-ending strikeout.

While Buehler fought to secure a spot in the playoff rotation, a lesser-possible option may have presented itself Saturday night in Salt Lake City when Tony Gonsolin, in his third rehab start for Triple-A Oklahoma City, threw 45 pitches in three hitless innings with six strikeouts and one walk.

Gonsolin underwent Tommy John surgery a year ago, but Roberts said before Saturday’s game that the 30-year-old right-hander and 2022 All-Star could be a candidate for the postseason rotation or bullpen.

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“He’s been good, so we just need to keep building him up,” Roberts said. “If this goes well, then I think a conversation about him coming to us at some point is more tangible.”

Gonsolin would have to start at least once for the Dodgers or Oklahoma City and throw 60 pitches in four innings before he would be considered for a spot in the rotation. But he does have experience in the bullpen, having made eight appearances as a relief pitcher from 2019-2021.

“The great thing about Tony is he’s done both, and I think there’s value in both,” Roberts said. “The first priority is to get him right, build him up, and then we’ll assess where our staff is overall.”

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This story originally appeared in the Los Angeles Times.