Just to throw an additional wrench into the mayhem surrounding Roy Halladay and the various trade possibilities he is involved with. it appears that if the Blue Jays’ ace is traded before this year’s July 31 trade deadline, he could walk at the end of the 2009 season.

According to a report by MLB.com Phillies’ beat writer Todd Zolecki, players who signed multiyear contracts before October 2006 and are traded in the middle of their deals, can demand a trade. According to Zolecki, Halladay signed a three-year, $40 million contract extension with the Blue Jays in March 2006. That means if Toronto trades him, he can demand a trade in the off-season. If Halladay were to demand a trade and the Phillies didn’t trade him, Halladay would become an unrestricted free agent March 15. He would also get to choose six teams in which he would not accept a trade, further complicating matters.

Therefore, if Phillies’ GM Ruben Amaro, Jr. trades Kyle Drabek, Michael Taylor, J.A. Happ, and/or Lou Marson/Jason Donald, there is the possibility that they would all have been traded for a two or three month rental. That is exactly what happened to the Brewers last season when they traded for C.C. Sabathia, only to watch him sign with the Yankees in the offseason. While the circumstances were different in the Sabathia case (he was a free agent at the end of last season and the Brewers knew they were a long shot at re-signing him), it was an aggressive gamble with hopes that the move would help them to the World Series.

That being said, Halladay is looking to play for a team that can seriously contend for a World Series championship, and there are few teams better suited to do that than the Phillies. Zolecki believes there is little chance that Halladay would make that trade demand, and I agree, but it is still something to consider.