Rodriguez, who led the club in wins (14), starts (33), innings pitched (205 2/3) and strikeouts (193), still nearly doubles his salary from the $2.65 million he made in 2009. Arbitrators Richard Bloch, Elizabeth Neumeier and Frederic Horowitz made their decision after hearing the case on Wednesday at the Renaissance Vinoy Hotel in St. Petersburg, Fla.
"We're pleased with the decisions," Astros general manager Ed Wade said. "We're happy the process is now over and we're in position to get our guys ready for baseball. Our primary focus is to get the club ready, and Wandy will play a big part."
Rodriguez sat in on the four-hour hearing with his agent, Barry Praver, who didn't return a phone call seeking comment. The Astros were represented by Wade, president of baseball operations Tal Smith and assistant general managers Ricky Bennett and David Gottfried.
"It went very good and 99.9 percent of the time, they're very professional," Wade said. "Both sides did a very professional job with their presentations. Arbitration is part of the process to determine a fair salary."
Astros pitchers and catchers will work out for the first time on Saturday in Kissimmee, Fla. Rodriguez is slotted as the club's No. 2 starter behind ace Roy Oswalt, who went 8-6 last year.
"I had a chance to talk to [Rodriguez] afterward and told him no matter what the decision, tomorrow the focus is on baseball," Wade said. "He was fine. Hopefully he comes in with the right attitude."
Rodriguez, 31, has a career 51-52 record with a 4.33 ERA and has made at least 20 starts of each of his five Major League seasons. He finished ninth in the National League last year in ERA and was 10th in strikeouts per nine innings.
The Astros have not lost a case since 1996 (Rick Wilkins). They beat Mark Loretta and Jose Valverde in 2008, but their most recent case to go to hearing a prior to that was with Darryl Kile in '97.
Houston had eight arbitration-eligible players this year and avoided a hearing with all but Rodriguez. Those eight players will make a combined $16.84 million this year, which represents a more than $10 million raise from their combined 2010 salaries.
Brian McTaggart is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.