Nate Robertson could become a free agent after the 2009 season, but he wants to remain in the Tigers' starting rotation longer than that. Robertson's agent Steve Canter said this week that Robertson would like to sign a long-term contract with the team this winter. "He wants to stay in Detroit and play for the Tigers," Canter said in a telephone interview. "He appreciates everything they've done for him and his family." "He's a proven guy in big games. He finished strong this year. If you look at what he's done career-wise, it's pretty significant." Robertson, a 30-year-old left-hander, was offered salary arbitration last week. So, even if he does not sign a long-term deal, Robertson will receive a raise over the $3.26 million he earned last season when he went 9-13 with a 4.76 ERA in 30 starts.