The Astros, who got three players in return for Lowrie and relief pitcher Fernando Rodriguez, clearly gave up one of their top offensive players from a year ago, but they see enough in a Greene-Gonzalez combination that makes them feel comfortable at the position.
Gonzalez, who stuck with the club as a Rule 5 Draft pick a year ago, is a polished defensive player who held his own offensively in 2012, hitting .234 with two homers and 12 RBIs. Greene, acquired in a trade with the Cardinals last August, hit a combined .230 with 11 homers and 30 RBIs with St. Louis and Houston.
"Those two guys are the front-runners," Luhnow said. "Jake Elmore will be in the mix as well. We claimed him [from Arizona] and feel confident he can play shortstop. Those are three players that will be there, and we'll be monitoring the trade market and whatever unsigned free agents there are in case we feel like we need someone."
Elmore, 25, hit .344 with 30 doubles, 73 RBIs, 32 stolen bases and a .442 on-base percentage in 108 games for Triple-A Reno last season. He made his Major League debut with Arizona in August and played in 30 games for the D-backs, including 14 starts at shortstop and one at second base. He was named a Pacific Coast League midseason and postseason All-Star.
"We're pretty set at shortstop, and it's a position we have some flexibility with Greene and Gonzalez already in the pipeline, and it allows us to upgrade at other positions," Astros manager Bo Porter said.
Beyond the Major League club, the Astros could be set at the position for years. Jonathan Villar remains one of their top prospects and will be at Major League camp again this year. He has plenty of tools, but remains raw and lost valuable at-bats last year after breaking his right hand punching a door on July 13 with Double-A Corpus Christi. He returned to action Sept. 6.
Of course, Houston's shortstop of the future is Carlos Correa, the No. 1 overall pick in the 2012 First-Year Player Draft. He made his professional debut at 17 years old last year, and hit a combined .258 with three homers and 12 RBIs with the Gulf Coast League Astros and rookie-league Greeneville after a slow start.
Correa, who will play his first full season in pro ball this year, is still a couple of years away from making an impact on the Major League club. For now, the Astros are casting their lot with Greene and Gonzalez and hoping for the best.
"We're hopeful one of those guys grabs the bull by the horn and takes that shortstop position," Porter said. "From a managerial standpoint, the luxury for me is Marwin is a switch-hitter. He's probably better from the left side than right-handed. Tyler Greene is right-handed. It gives us confidence knowing we have two guys on our roster that if need be, they could be in a platoon situation, which gives you a pretty solid everyday player."