The Astros' top prospect, who wears No. 24, put together his first four-hit game of the season on April 24. One month later, on May 24, he did it again.
Singleton went 4-for-5 with a homer and four RBIs on Thursday night, helping the Double-A Corpus Christi Hooks rout the Arkansas Travelers, 13-4.
The 20-year-old first baseman started his day with an RBI single in the first, then came through with another run-scoring single in the third. He homered later in that inning, sending a two-run shot over the right-field wall to cap a franchise record-tying nine-run frame for the Hooks.
Singleton recorded his final hit in the sixth, leading off the frame with another single, then struck out in his final at-bat in the eighth.
Selected by the Phillies in the eighth round of the 2009 Draft, Singleton hit .284 with nine homers in 93 games at Class A Advanced Clearwater last year. He was traded to Houston along with three other players in exchange for Hunter Pence on July 29, after which he batted .333 with four homers in 35 games for the Lancaster JetHawks.
He has carried over his hot hitting into this season, and he is now batting .316 with six homers in 43 contests. Overall, he has hit .324 with 10 longballs and 44 RBIs in 78 games since the trade.
No. 2 Astros prospect Jarred Cosart (3-2) earned the win after scattering four runs on 12 hits over seven innings. He struck out six and walked two.
Hooks catcher Ryan McCurdy contributed to the nine-run inning by hitting a grand slam on the first pitch he saw. The 24-year-old catcher, who is playing in his third season with the Astros after spending four years at Duke University, had not hit a home run at any level since his senior year of high school.