SAN DIEGO -- From the moment they acquired him as their Trade Deadline prize, the Padres envisioned handing the ball to Mike Clevinger for the franchise's first playoff game in 14 years.

They're now one week away from the start of the National League Wild Card Series. Suddenly, Clevinger's status for the postseason is in serious doubt.

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The right-hander exited the Padres' 5-2 loss to the Angels on Wednesday afternoon after just one inning due to a flare-up of the biceps tightness that caused him to be scratched from Saturday's start. He underwent further tests, including an MRI exam, and as of Wednesday postgame, the Padres were awaiting results.

“We’re going to wait for the results and see what the doctors say,” Padres manager Jayce Tingler said when asked whether Clevinger’s postseason status was in jeopardy. “I don’t want to speculate or anything like that because I just honestly don’t know.”

Clevinger worked a 1-2-3 first inning, showing no visible signs of any ailment. But he didn't emerge for the second and was replaced by Adrian Morejon -- who would surrender four runs on three homers in the second inning. Tingler revealed that Clevinger’s biceps tightened on the first curveball he threw, to Angels No. 2 hitter Jared Walsh.

It’s the same tightness that forced Clevinger to miss Saturday’s start, Tingler said. But Clevinger threw a bullpen session on Monday and didn’t feel any pain.

“He threw his bullpen; everything was good,” Tingler said. “He felt good in the bullpen today, and to start the game, he said he felt good. It was the first curveball he threw to Walsh.”

Clevinger was acquired to solidify San Diego’s rotation as one of the best in baseball, and he’s done that. He arrived in a nine-player blockbuster on Deadline Day and has posted a 2.84 ERA in four outings since. Two through five, the rest of the rotation has filled in seamlessly behind him.

If Clevinger is unavailable, the Padres aren’t too worried about that Game 1 start. They would presumably hand the ball to NL Cy Young Award candidate Dinelson Lamet on his usual four days’ rest. Lamet, who owns a 2.07 ERA and is a contender for the NL strikeout title, has been their most dominant pitcher this season.

After Lamet, however, things get murkier. Zach Davies and Chris Paddack would presumably serve as options for Games 2 and 3 in Clevinger's absence. Right-hander Garrett Richards has already transitioned to the bullpen, and Tingler said those plans haven’t changed.

“It’d be a big blow if we lost Clev,” said first baseman Eric Hosmer. “... He’s fit in extremely well with this team.”

Before Clevinger's early exit on Wednesday, the Padres’ injury news had mostly been positive. They’d welcomed Hosmer (fractured left index finger) and Tommy Pham (broken left hamate bone) back to the team over the past few days.

It's imperative that the Padres get that duo going ahead of the playoffs, and Wednesday offered a small bit of positive news in that regard. Hosmer went 2-for-4 and launched an opposite-field two-run homer off Angels starter Jaime Barria in the first inning.

That was all the offense a slumping San Diego offense would muster. The Padres were unable to close in any further on home-field advantage in the first round, leaving their magic number at two. They have now dropped five of seven, averaging 3.4 runs per game in that span -- down from 5.7, their season average beforehand.

"We've got four more games, and we've got to get back and get going on a lot of cylinders," Tingler said. "I feel confident we're going to get out of this shortly. … We’ve just got to be planning on playing our best ball starting on Wednesday.”

With or without Clevinger.