DETROIT -- Manager Bo Porter knows he has at least two everyday players in third baseman Matt Dominguez and second baseman Jose Altuve. He wants to discover if he has the same in his outfielders.
That's why the manager named Robbie Grossman, J.D. Martinez and Jimmy Paredes the team's three regular starters, rather than continue shuffling the trio in and out with Trevor Crowe and Brandon Barnes.
"They're going to get the bulk of the playing time," Porter said on Monday, "so that I, as a manager, can make a definitive decision as a manager to answer the question: Can this guy or can that guy play every day at the Major League level?"
Porter said answering that question's been the goal since entering the season.
So far, the verdict is still out. Grossman entered Monday hitting .194 in 17 games this season, but he singled to lead off Monday night's 7-2 loss against Detroit and finished 2-for-4 with an RBI an a run. Martinez was hitting .203 in 19 games, and also went 2-for-4 on Monday, and Paredes stood at .182 through six, and was 1-for-3 with a walk.
Porter needs a bigger sample size.
"We're going to give those guys a chance to prove it one way or another, "Porter said. "Because I don't have enough information at this point in the season."
He also said it doesn't necessarily mean Crowe and Barnes won't ever see the field.
"I took the opportunity to talk to Barnes and Crowe today to let them know my decision," he said. "I told them I'm not going to leave them sitting for long periods of time."
Porter, Astros surprised by Postolos resignation
DETROIT -- Manager Bo Porter and the Astros players were as surprised as anyone upon hearing the news that team president and CEO George Postolos announced his resignation Monday afternoon.
The team had just arrived at Comerica Park, set to begin a six-game road trip with the first of three games in Detroit when they were informed.
"I was shocked," Porter said before his team's fifth straight loss, a 7-2 decision to the Tigers. "I got to the ballpark and the information was dropped on me. It's obviously completely out of my jurisdiction. I don't even know what happened and what led to his resignation."
Postolos had held his position since November 2011. He was instrumental in owner and chairman Jim Crane's acquisition of the franchise in May 2011, teaming with Crane to make it possible.
He was also the key figure in the Astros' rebranding this season, including new uniforms, colors and logo, according to a statement released by the team.
"It happened so soon into the season," said right-hander Lucas Harrell, who is slated to start Tuesday's game. "I think that's what caught a lot of people off guard is the quickness of it."
Others in the clubhouse chose not to get into it. Second baseman Jose Altuve said he had few thoughts on the matter, other than it also surprised him. Instead, he elected to focus on the team, which is trying to rebound from a 2-8 homestand.
Porter, speaking with the media prior to Monday's game, took the same stance.
"It's definitely something from an organizational standpoint that, these things happen in sports," Porter said. "It's all part of it and you let the people in charge of dealing with those situations … you let them deal with it."
Astros take first trip to Comerica as AL team
DETROIT -- The last time the Astros played a game in Comerica Park, Roger Clemens, Andy Pettitte and Wandy Rodriguez were the team's starting pitchers.
It was seven years ago when Houston last traveled to Detroit -- a year in which they finished second behind the Cardinals in the National League Central.
Times have certainly changed, as the team has since moved to the American League and, entering play on Monday, had baseball's worst record at 10-28.
For the Astros, a 7-2 loser Monday night, perhaps their biggest asset in the series will be Carlos Pena. The 34-year-old first baseman and designated hitter considers Detroit something of a second home. He spent four years playing for the Tigers, from 2002-05.
"I've spent a big part of my career here in Detroit and I have many memories," he said. "I'm so grateful for the opportunity they gave me when I was younger. It's just always good to come back and see old friends. It's just got a special place in my heart."
That experience in Comerica Park could actually prove useful in the series, as very few of his current teammates have played there.
"It plays big," he said, "especially to center field. Similar to our home park in Houston."
The distance to straightaway center field is 420 feet, second to only Minute Maid Park (436) in the Majors. The Red Sox also have a triangle which juts out to 420, but it's a much smaller area.
It provides a unique challenge for the outfielders, but it has the batters such as second baseman Jose Altuve excited to take his hacks.
"It's pretty big. A lot of room to hit the ball," said Altuve, who entered the game tied for third in the AL in hits (51) with Baltimore's Adam Jones. "I feel really good once I [took] my [batting practice], and I really like the field."
Gonzalez turns outing around in a hurry
DETROIT -- Edgar Gonzalez's return to the Astros appeared to be heading for disaster.
The 34-year-old reliever, who appeared in six games for the club last season and was re-signed when the team designated Philip Humber for assignment, allowed four runs in his first inning back with the team, against Texas on Sunday.
The inning included a leadoff homer by Leonys Martin and was capped by a three-run blast from Adrian Beltre to make the score 12-1.
However, the right-hander recovered and fired three scoreless innings after that, retiring nine of the final 11 batters he faced.
Gonzalez admitted to being a little bit nervous and unsteady with his first pitches, but he was more shocked with the aggressiveness of the Rangers' hitters with a seven-run lead.
"The score was like 8-1 and I didn't know they were going to swing at every pitch," he said. "I thought they were going to wait a little bit and see how I'm throwing, but no, they just swing at everything.
"They surprised me a little bit, but after that I made an adjustment and started throwing different the last three innings. So that made the difference."
The damage had already been done against Texas, but his recovery gave the bullpen a much-needed rest before what could be a busy series against Detroit.
• Rick Ankiel, who was designated for assignment and released by the Astros last week, signed a Major League deal with the Mets on Monday. He was in their starting lineup playing center field and batting seventh against the Cardinals.
"I am absolutely elated for Rick," manager Bo Porter said. "It's good for him and I think he'll be able to help their ballclub."
Anthony Odoardi is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.