Thursday's Pacific Coast League game between Oklahoma City and New Orleans was supposed to be headlined by the Triple-A debut of top Marlins prospect Andrew Heaney, and the left-hander didn't disappoint.

Heaney struck out seven batters and held the RedHawks to one run on seven hits over five innings. But he was outpitched by right-hander Nick Tropeano, the Astros' No. 17 prospect.

Tropeano struck out eight batters and held the Zephyrs to only three hits over 6 2/3 scoreless innings in a game New Orleans went on to win, 3-2, in 10 innings.

Tropeano, who led all Astros Minor Leaguers in strikeouts in 2012, lowered his ERA to 2.53 with his third straight start of six or more innings with two or fewer runs.

After posting a 2.36 ERA in his 2011 debut and racking up 166 strikeouts in 2012, Tropeano seemingly took a step back in 2013, finishing 7-10 with a 4.11 ERA with Double-A Corpus Christi. But the 23-year-old right-hander is off to an encouraging start in 2014, as evidenced by his latest outing Thursday night.