BATON ROUGE — LSU has so much pitching depth, coach Paul Mainieri is concerned that if he starts a second-line pitcher Friday, it may hurt the feelings of NCAA Regional opponent Texas Southern.

Must be nice.

The No. 4 national seeded Tigers (43-17) host Texas Southern (20-32) at 2:30 p.m. Friday at Alex Box Stadium on the SEC Network in the opener of the NCAA Baton Rouge Regional at Alex Box Stadium. LSU’s team earned run average is 3.60, and each of its top nine pitchers have an ERA of 3.86 or lower with four under 3.00.

Texas Southern has a 6.56 ERA on the season and is at 8.07 against non- Southwestern Athletic Conference teams. It has one pitcher with an ERA under 4.50 — left-handed reliever Robert Loza, who is 2-1 with a 3.95 ERA and one save. These Tigers are hitting .256 as a team. So, the thought process is … do not waste a very good pitcher against a team like this.

LSU’s No. 3 weekend starter — freshman right-hander Eric Walker at 7-1 with a 3.78 ERA — is not available for Friday’s game anyway as he threw 116 pitches through seven and two-thirds innings on Sunday in beating Arkansas, 4-2, for the Southeastern Conference Tournament championship in Hoover, Alabama. He would have just four days of rest if he started Friday. He has gotten six days rest between starts this season.

“Eric’s not a candidate for Friday,” Mainieri said. “He could go Sunday.”

Mainieri is holding ace junior right-hander Alex Lange (8-5, 2.59 ERA) for the “marble” game — aka winners’ bracket game at 7 p.m. Saturday that will pit the LSU-Texas Southern winner versus the Southeastern Louisiana-Rice winner from the 7 p.m. Friday game. Lange last pitched on Thursday, throwing 92 pitches in a seven-inning, 10-run rule, 10-0 win over Kentucky and has been on a roll of late.

That leaves the weekend No. 2 starter — senior left-hander Jared Poché (10-3, 3.18 ERA) — as an…