SAN DIEGO -- Whether Mike Clevinger pitches for the Padres this October might depend on how deep the Padres play into October.

Clevinger, who exited his start Wednesday with right biceps tightness, underwent an MRI exam and was further evaluated by the Padres’ medical staff on Thursday. The team is proceeding as though it’s unlikely Clevinger will make his start in the National League Wild Card Series next week. But an October return has not been ruled out.

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An official announcement regarding Clevinger’s injury is expected Friday, before the Padres’ doubleheader in San Francisco. A team spokesperson indicated that “any speculation at this time would be premature,” given that Clevinger will be evaluated further before an announcement is made.

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In any case, the Padres are less than a week away from the start of their first postseason in 14 years, and they might be without their prize Trade Deadline acquisition, at least at the start. Here’s what it means:

What does it mean for Clevinger?

It's been a season of fits and starts for Clevinger. He went three weeks without appearing in a game earlier this year after being placed on the restricted list for violating health and safety protocols. Then, he endured a topsy-turvy Trade Deadline and didn't pitch for eight days -- a couple of which were spent packing and travelling.

Clevinger had finally found a rhythm when he shut out the Giants over seven innings on Sept. 13, lowering his ERA to 3.10.

Then his biceps barked. He was scratched from his start Saturday but reported a pain-free bullpen session on Monday. That lined him up for a start Wednesday against the Angels, and on a first-inning curveball to Jared Walsh, it barked again.

The next step for Clevinger is unclear. But he hasn’t thrown more than one inning since Sept. 13, stalling twice. His health will be paramount, team officials have said.

The Padres have reason not to rush Clevinger back. They acquired him in a pricey nine-player blockbuster, and Clevinger has two years remaining in San Diego before he hits free agency.

What does this mean for the Wild Card Series?

The right-hander was in line to start Game 1, but the Padres could use Dinelson Lamet in his place on normal rest. Lamet is slated to start the second game of Friday's doubleheader.

There’s hardly a drop-off from Clevinger to Lamet, who owns a 2.07 ERA and is chasing the Reds’ Trevor Bauer for the NL strikeout title. There's a case that Lamet is the Padres' ace, even with Clevinger.

The impact will be felt in Game 2. Chris Paddack was presumably on the outside of the Padres' Wild Card Series rotation. Now, he’s expected to be thrust into that Game 2 start in Clevinger's place.

It's been a roller-coaster season for Paddack, who is coming off six one-hit innings against Seattle. He has mixed a few of those excellent starts with a handful of duds. In a three-game series, the Padres can't afford a dud. They'd planned to avoid that volatility by saving Paddack for the NL Division Series.

If Zach Davies starts Sunday, as expected, he'd be lined up to pitch Game 3, as originally planned. (Davies has had a sneaky excellent season, with a 2.85 ERA and no more than three earned runs allowed in any of his 11 starts.)

What does this mean for the Padres’ overall playoff picture?

The Padres were planning for a four-man playoff rotation, adding Paddack to the mix after using Clevinger, Lamet and Davies in their best-of-three. If the No. 5 spot in the rotation came up, they'd ask one of their starters to work on three days’ rest or they’d fashion a bullpen game.

With that roadmap, the Padres moved Garrett Richards to the bullpen earlier this month. They planned to use him as a righty weapon and a long man.

Now, it's wholly unclear what Richards' role is. It's not as simple as sliding him back into Paddack's spot. In seven of his last eight outings, Richards has thrown 65 pitches or fewer. It'd be unfair to expect him to take the ball and work seven innings.

The Padres might still ask Richards to assume the No. 4 spot in their rotation -- but as a four- or five-inning option, before they turn the ball over their bullpen (a common occurrence in the postseason anyway).

If they do that, it might make an all-out bullpen game untenable for the fifth spot in the rotation. Of course, that spot might not arise until Game 5 of the NL Championship Series, and the Padres wouldn't mind facing that conundrum.

The best answer, of course, would be a healthy Clevinger.