LSU’s search for a third starter unfolded at Alex Box Stadium on Tuesday afternoon.

One by one, each LSU reliever went to the mound for a brief simulated game against the Tigers’ hitters. Parker Bugg began things around 1 p.m. Nine pitchers later, Hunter Devall finished off the live session about 90 minutes later.

Three days ahead of the start of the Baton Rouge regional, LSU is in an unsettling position: It doesn’t have a third starting pitcher. Coach Paul Mainieri admitted Tuesday that he’s concerned about that issue as the NCAA postseason creeps closer.

The consensus top-ranked team in the land and the No. 2 overall NCAA national seed, LSU (48-10) might approach Friday’s regional opener against No. 4 seed Lehigh (25-29) as it has midweek games, using several relievers in what Mainieri terms the “Jack Wholestaff” method.

“Don’t be surprised if there’s a lot of pitchers throwing on Friday,” the coach said. “I’ll put it that way.”

Freshman ace Alex Lange will start in LSU’s second game of the regional — presumably in the winners’ bracket final Saturday night against the Tulane/UNC-Wilmington winner. Mainieri revealed Tuesday that sophomore Jared Poché will start Sunday in what could be an elimination game or the regional championship.

Who starts Friday? Who knows? But it may not matter if the Tigers plan on using five to seven pitchers in a piecemeal type of way.

The weather forecast Friday calls for a 60 percent chance of rain. That could dictate the Tigers’ pitching plan against the Mountain Hawks, who sport an NCAA RPI of 239.

“There are a lot of different options the way we can do Friday,” Mainieri said. “The weather may play into it as well. If it’s going to be one of those days, (where) scattered showers might start and stop, we may try to piece it together instead of just identifying one starting pitcher having to go out there.”

Mainieri and pitching coach Alan Dunn watched closely Tuesday as 10 relievers pitched in live sessions against LSU’s hitters in an effort to choose a plan for Friday’s game.

“We’re going to see how the guys throw and think about it a little bit more and probably know for sure on Thursday who will start on Friday,” Mainieri said before the live pitching.

LSU is, somewhat, in this mess after freshman Austin Bain of Dutchtown couldn’t make it through the second inning of his most recent start at the Southeastern Conference tournament — a second performance of fewer than two innings in three weeks.

It continued the struggles of LSU’s No. 3 starter this season. The Tigers’ third weekend starters — counting Bain’s outing in Hoover — have an ERA of 4.75, have struck out 36, have walked 31 and have allowed 61 hits in 53 innings. It has been a season-long issue for a squad that has used four No. 3 weekend guys: Kyle Bouman, Jake Godfrey, Zac Person and Bain.

“Our third starter I’m a little bit more concerned about,” Mainieri said in response to a question about LSU’s starting pitching. “Bain threw so well against South Carolina, and the other day he didn’t pitch well at all. More than not pitching well, I didn’t like his mound presence, his tempo. He just didn’t look like a kid showing a lot of poise the other day. He looked like a true freshman.

“Whether or not this is too big for him for opening day or not is something I’ve got to work my way through this week.”

So, yes, Bain is still an option for Friday’s game. In fact, he was one of three pitchers who did not participate in Tuesday’s live pitching. The other two: Poché and Lange.

LSU is saving those two — its top two starters — for the two most important games against the two better teams in the regional. It’s a risk that LSU didn’t take last season in a regional the Tigers eventually lost.

Jared Poché, the Tigers’ No. 2 starter last season, threw the regional opener against Southeastern Louisiana, one of the NCAA tournament’s better No. 4 seeds last year. LSU saved ace Aaron Nola for Saturday night’s winners’ bracket final.

The Tigers won both of those games before losing the last two games of the regional to Houston in starts made by No. 3 pitcher Bouman and a volley of relievers in Game 4.

This year, things are different.

LSU’s offense is third nationally in batting average and leads the SEC in nearly every offensive category. Its pitching staff is much deeper, with two to four more power arms than the 2014 club.

Even shortstop Alex Bregman admitted that.

“I think we’re a better team than we were,” he said. “I think we’re more of a complete team.”

So, Mainieri is possibly turning to Jack Wholestaff for a Game 1 start against a Lehigh team that’s batting .266. LSU has proved over the past several seasons that using multiple pitchers — none usually more than two innings — is a recipe for success.

The program has used the approach for midweek games since Dunn took over as pitching coach in 2012, and the Tigers are 53-3 in midweek games in that time.

“We have a track record with that,” Dunn said.

Using multiple relievers Friday could affect the rest of the weekend, right? Dunn isn’t sure.

“It’s hard to answer that question until you see what you do in that game,” he said. “Does this guy throw ‘X’ amount of pitches? Do you think he’s still going to be sharp? There’s guys who can pitch two or three days in a row, and you have to be able to do that out of the bullpen.

“You just have to manage the game, how you use them and how much they have pitched and what’s their confidence level and how they’re going to rebound for the next day.”

Follow Ross Dellenger on Twitter @DellengerAdv.