CONWAY, Ark. — Jesuit-based Retif Oil rode its defense and the arm of Davis Martin early before getting its bats going Thursday in an 11-2 win over Tupelo (Mississippi) on Thursday in the second round of the Mid-South Region American Legion Tournament at Hendrix College’s Warrior Fields.

Retif (28-6-1) will play Oklahoma at 7 p.m. Friday in the winners bracket final. Tupelo (17-15) drops to the losers bracket and will face the Bryant (Arkansas) Black Sox in a 3:30 p.m. elimination game.

The double-elimination tournament will continue through Sunday.

Martin, a junior at Jesuit, allowed two runs and nine hits, struck out three and walked none in earning the complete-game win. The Retif defense backed him up, committing just one error — a close call in the seventh inning — and turning a pair of 5-4-3 double-plays.

“Davis getting that complete game is really big,” Retif coach Joey Latino said. “That saves our bullpen. He pounded the strike zone, and we let our defense play behind him.”

Martin said he had struggled with arm problems all summer but came out Thursday feeling good.

“I told coach, ‘I’m going to get you nine innings,’ ” he said. “Our strategy was to throw strikes and let our defense back us up.”

Ben Hess’ diving catch in right field for the final out of the first inning set the tone early for Retif, as did a couple of Dan Edmund scoops at first.

In the top of the second, after giving up a leadoff single, Retif turned its first double-play, which helped it escape unscathed.

Retif Oil scratched out its first two runs in the bottom of the third. Josh Schmidt walked and advanced to second on an error on the Tupelo pitcher. Brandon Briuglio delivered a two-out RBI single and later scored on Trent Forshag’s single for a 2-0 Retif lead.

With Martin facing just four batters in the top of the fourth, Retif blew the game open in the bottom of the inning. Retief sent 11 batters to the plate in the inning, which yielded seven runs and seven hits. Edmund had two singles in the inning; Stephen Sepcich delivered an RBI triple, and Nick Ray, Briuglio and Hess recorded singles. Scott Crabtree had a double, and Forshag and Schmidt had sacrifice flies in building the 9-0 lead.

“The big inning is a good thing, but it’s also a bad thing,” Latino said. “I don’t want to say we got complacent, but it was hard to keep our enthusiasm and intensity after that inning.”

The top of the sixth marked the first time Tupelo got a man to second base. Ty Wheeler’s double scored Henry, who had singled, to bring the 49ers within 9-1, but Retif got the run back in the bottom of the inning when Hess walked, went to third on Forshag’s single and scored on Edmund’s groundout. After six, Retif led, 10-1.

The 49ers scored their other run in the top of the seventh. Cody Pate led off with a double to left and went to third on the first Retif error of the tournament. Austin Grubbs’ single to left scored Pate, 10-2. Once again, though, Retif turned a double play to stifle any momentum.

The final margin came in the bottom of the eighth when Hess walked, advanced on a pair of wild pitches and scored on Crabtree’s sacrifice fly to center field.

After two days, Retif is in good shape to win the tournament it won in 2012. The regional winner will advance to the World Series in Shelby, North Carolina, beginning Aug. 13.

“I’m very confident that we have a great chance of winning this tournament,” Martin said. “We came here with one goal: to make it to North Carolina.”