BATON ROUGE, La. – Senior right-hander Zac Cowan fired four scoreless relief innings Tuesday night, and centerfielder Derek Curiel smashed two doubles and a homer, leading LSU to a 12-4 win over Southeastern Louisiana in Alex Box Stadium, Skip Bertman Field. LSU improved to 25-21 on the year, while Southeastern dropped to 28-18. The Tigers return to action at 6:30 p.m. CT Friday when they open a three-game SEC series against South Carolina in Alex Box Stadium, Skip Bertman Field. Friday’s game will be broadcast on the LSU Sports Radio Network and streamed on SEC Network + “This was one of our best games in a while against a good team that is in first place in the Southland Conference,” said LSU coach Jay Johnson. “Zac Cowan is the most reliable pitcher you could ever ask for, and our offense continued to score runs in may different ways.…