Greene, in his first appearance in St. Louis since being traded on Aug. 9, took a wrong turn in an effort to locate the visitors' locker room for the first time.
"I never had to go past the home clubhouse in the hallway there," Greene said. "A little lost at first. I had no idea exactly where it was."
Greene returned to St. Louis with mixed emotions after spending the first seven years of his career in the Cards' organization. St. Louis' first-round pick in the 2005 First-Year Player Draft, Greene was sent to Houston for cash considerations and a player to be named 12 days ago.
So far, the move has worked well for Greene, a part-time player with the Cardinals who has moved into the starting lineup in Houston.
Greene is hitting .355 with two homers and four RBIs in nine games with the Astros. He carried a .645 slugging percentage into the first game of a three-game series on Tuesday. Greene, who is relishing the chance to play every day, was hitting .218 at the time of the trade.
"It's been an opportunity to get four or five at-bats every day and get some consistent playing time," Greene said. "It's been a big breath of fresh air for me.
I'm excited about the new start."
The Raleigh, N.C., native played a career-high 58 games for the Cards in 2011. He hit 212 with one homer and 11 RBIs.
Greene got a chance to catch up with some of his former teammates Tuesday. He came to St. Louis on Monday to clean out his apartment and take care of some personal business.
The 29-year-old harbors no ill will toward the Cardinals and says he will always look back with pride on his years with the organization.
"I was able to experience two playoffs here, a World Series and I enjoyed everybody, from the players to the front office," Greene said. "It's a great organization. I have no regrets. Now, it's time to move on and I'm excited about the next step in my career."
Greene immediately caught the eye of Houston fans with a 2-for-5 performance in his first start. He hit a home run in a 6-5 win over Milwaukee. He has started six games at shortstop and one at second base.
Houston general manager Jeff Luhnow, who helped draft Greene during his front-office stint with the Cardinals, is not surprised by Greene's success in his first week.
"Sometimes, just a new beginning is all it takes," Luhnow said.
St. Louis manager Mike Matheny says he wishes Greene all the best.
"He's a talented player, I hope things click for him," he said.