All season, fifth-year starter Luke Harrison has been a relatively steady presence for the Longhorns. While not perfect, he’s remained reliable. He entered Sunday’s r ubber match against Mississippi State with a 3.93 ERA and a résumé that included some of Texas’ strongest outings this season — including a seven-inning, scoreless performance against Ole Miss. But with that consistency has come some volatility. Most notably, Harrison was tagged for eight runs in the first inning against Texas A&M earlier this season.  On Sunday, oddly enough, both versions of Harrison showed up on the mound. And in the end, the one Texas needed most took over. Behind a resilient outing from Harrison and a massive third-inning offensive explosion, the Longhorns erased an early deficit and rolled to an 11-6 win over No. 10 Mississippi State at UFCU Disch-Falk Field, securing their seventh SEC series victory of the season.…