The remaining Astros on the Top 100 are shortstop and 2012 No. 1 overall Draft pick Carlos Correa (30), outfielder and 2011 first-round pick George Springer (57) and right-hander Jarred Cosart (89), who is Houston's top pitching prospect. Singleton and Cosart were among four players acquired by the Astros from the Phillies in the Hunter Pence trade in 2011.
"It's a tribute to the work put in by [GM Jeff Luhnow] and the previous regime and the scouting department, [scouting director] Mike Elias and that crew, as far as bringing in talented players to help replenish the system," Astros director of player development Quinton McCracken said. "Having four guys there in the rankings of the top 100 prospects in baseball, that's a testament to the work put in the last few years."
Singleton will serve a 50-game suspension to start the season after testing positive for marijuana, which marked his second failed drug test. He will participate in Minor League camp, but the Astros still believe he could reach the Majors this year.
A left-handed hitter with power who's a good defensive first baseman, the 21-year-old Singleton hit .284 with 21 homers and 79 RBIs last year in 131 games at Double-A Corpus Christi. He'll likely begin the season at Triple-A Oklahoma City once his suspension is over in May.
Correa was the youngest player in the Draft when the Astros took him first overall last June, and he performed well in his debut after a slow start. He appeared in 39 games in the rookie-level Gulf Coast League before going to Greeneville of the rookie-level Appalachian League for 11 games, hitting .258 with three homers, 12 RBIs and six steals combined.
Correa's range, arm and defensive actions are all above average. The Puerto Rican Baseball Academy product and the highest selection from the island also has the chance to be an impact hitter, as he has tremendous raw power and excellent bat speed.
"I've been working hard to have a good season this year with the Astros in the Minor Leagues," Correa said. "I feel really prepared to do a good job this year."
Springer, taken No. 11 overall in 2011 out of the University of Connecticut, is an athletic center fielder with five-tool potential. In his first full season in professional baseball last year, he hit .318 with 10 triples, 22 homers, 82 RBIs and 28 stolen bases at Class A Lancaster before finishing the season with Corpus Christi.
It's not uncommon for players to post big numbers in a hitter-friendly environment in Lancaster, so this will be an interesting year in Springer's development. He's expected to begin the season at Corpus Christi.
"It's a new year and a fresh start, and I'm excited about it," Springer said. "I'm going to try to work on slowing everything down and not try to be somebody I'm not. I need to not try to do too much in certain situations."
Cosart, 22, possesses one of the best fastballs in the system and will come to Major League camp for the first time this year, though Luhnow anticipates Cosart will start the season in the rotation for Oklahoma City.
Cosart made 15 starts at Corpus Christi and then pitched in six games (five starts) at Oklahoma City while battling blister problems in 2012. He went a combined 6-7 with a 3.30 ERA in 114 2/3 innings, allowing 109 hits and striking out 92 batters.
Cosart's numbers in the Arizona Fall League weren't great -- 0-3, 6.50 ERA in six starts -- but he was working on commanding a third pitch.