Lesch was one of four Spartans who turned in multi-hit performances, as Erik Samples, Luke Weber and Zach Krider each registered two hits apiece. Weber and Stephen Dowling both drove in three runs to help Upstate score its most runs since plating 11 March 8 against LaSalle.
Freshman right-hander Eric Birklund secured his first career victory after giving up just one hit in three innings of relief. Jordan Miller pitched two strong innings before Samples came on in the ninth to preserve the win.
Jacksonville starter Alex McRae allowed eight runs on nine hits and walked five in 4.1 innings of work and suffered the loss. Zach Gordon and Nathan Disch each allowed a run in relief on McRae.
Scott Schaub delivered a two-run double and Nate Ricci added an RBI single in the first inning to help put Jacksonville ahead 3-0. A two-out triple from Ricci followed by a double from Dylan Dillard in the third inning gave the Dolphins a 4-0 advantage.
Upstate charged back in the bottom half of the third with four runs of a three-run double from Weber and a fielding error by Dillard in left field. Another error on the Jacksonville outfield in the fourth inning allowed Lesch to score from second and put Upstate ahead 5-4.
The Dolphins mounted a threat in the top of the fifth by putting the first two runners on after Michael Babb was hit by a pitch and Connor Marabell singled to center field. Upstate, however, responded by completing one of the rarest plays in baseball when Birklund induced Schaub to line into an inning-ending triple play.
The Spartans used a two-run triple from Dowling and an RBI single from Lesch to plate three more runs in the fifth and open up an 8-4 edge. Dowling added another RBI in the sixth inning with a groundout to score Weber with the ninth run of the night.
Babb picked up an RBI single in the seventh to pull Jacksonville within 9-5, but Samples smoked a triple over Babb's head in right field in the bottom half to score Lesch and put Upstate back ahead by five runs.
Upstate and Jacksonville resume the series Saturday at 2 p.m. from Harley Park.