"They (Toronto) were headed in a different direction," Stairs said. "I can understand that. It's tough leaving Toronto, being Canadian and playing for a Canadian team. But when they told me I was going to Philly I was like... 'nice.' Going to a ballpark where I enjoy playing in."
With Geoff Jenkins on the disabled list with a strained hip flexor, the Phillies needed a left-handed bat. Stairs had been designated for assignment by the Blue Jays on Thursday night.
"We lost Jenkins so we were short left-handed," Phillies general manager Pat Gillick said Saturday. "Consequently, (we) get an experienced guy that can play some and hit off the bench. Can't hurt.
"We had claimed him off waivers, so they couldn't do anything with him. The only place they could move him was to us. Either they had to take the deal with us or keep him on the roster."
Phillies manager Charlie Manuel said Stairs would help his team off the bench or could be used to give right fielder Jayson Werth or left fielder Pat Burrell some rest.
"His left-handed bat can definitely help us," Manuel said. Used mostly as a designated hitter, Stairs was hitting .250 with 11 homers and 44 RBIs in 105 games for the Blue Jays. Toronto will use the roster spot to give top prospect Travis Snider significant playing time the remainder of the season.
Backup roles have become quite familiar to Stairs, who broke in with the Montreal Expos in 1992 and will be joining his 11th major league team. And he'll be back in the National League where pinch-hitters get more chances because there here is no DH.
As a pinch-hitter during his career, Stairs has batted .279 (70-for-251) with 12 homers and 59 RBIs. He is batting .333 this season with three RBIS in pinch-hitting roles.
"I love pinch-hitting. It's a situation where you usually pinch-hit in a situation where the game is on the line," the 40-year-old Stairs said. If I'm here for a month and they want me to pinch-hit everyday that's fine by me, whatever it takes.
"It's fun to be in that atmosphere of being in the playoff race again. It's nice to see this team loose and having fun because I've been on teams before when you get in a race and everybody gets tight."
Gillick said the deal will be finalized when the season is over and the player to be named later - likely a minor league pitcher - is officially identified.
Stairs, a career .266 hitter with 252 homers, joined the Phillies at Wrigley Field where they dropped first two games of an important four-game set against the Cubs.
"It will be a good fit for Matt," said Blue Jays GM J.P. Ricciardi, who was in New York to see Toronto in its last trip to Yankee Stadium. "They had Geoff go down and needed someone off the bench. He should be able to help them."
To qualify for the postseason, a player must be on a team's major league roster before Monday. With the Blue Jays fading from contention, Ricciardi said more moves are possible.
"I think you'll see some things happen," he said. "They'll be minor things, but things could pick up in the next day or two."
AP Sports Writer Dave Skretta in New York and AP freelance writer Patrick Rose in Chicago contributed to this report.