FLOWER MOUND — Lightning and rain threw a changeup at the Class 5A regional baseball semifinal between Southlake Carroll and Flower Mound Marcus on Friday.So Dragons coach Larry Hughes used a changeup specialist to put an end to the series.Marcus was leading 2-1 Friday with Carroll at bat in the top of the third inning when the game was suspended by the weather.So on Saturday, Hughes sent Joe Heineman to the mound.Heineman held the Marauders scoreless in the final five innings, striking out five and giving up two hits as the Dragons closed the series two games to none with a 4-2 victory.In the regional final this week, the Dragons will face Arlington Martin, which beat Hurst Bell 4-3 to sweep that series.Carroll’s everyday shortstop, Heineman replaced ace Tyler Alexander, who threw 39 pitches on Friday.Heineman proved to be a capable replacement.The only pitcher Hughes had seen throw a changeup that well was legendary closer Trevor Hoffman.“It is a nasty, nasty pitch,” Hughes said.A double by right fielder Drew Brown and a two-run single by first baseman Nic Motley in the top of the third gave Carroll a lead it would not surrender. Carroll’s first run came Friday night in the second inning when center fielder Chris Altimont scored on Connor Combs’ sacrifice fly caught deep in foul territory in right field. Marcus’ runs were scored in the second inning, while Alexander was on the mound Friday, thanks to a two-run single by Austyn Laird. An error in the inning made the runs unearned.After Heineman entered in the bottom of the third, he faced just three more batters than the minimum. “I only have two pitches and my off speed is my best pitch, and it was really working today,” Heineman said. “I trust my defense and just wanted to pound the strike zone.”Carroll is 34-4 for the season. Marcus ends its season at 33-8.