Would he give up a run?
But Halladay not only lived up to the hype his first season with the Phillies in 2010, he exceeded expectations. He threw a perfect game against the Marlins in May, a shutout against the Nationals in September to clinch the National League East title and his first trip to the postseason, and a no-hitter in October against the Reds in Game 1 of the National League Division Series. He also won 21 games and the National League Cy Young Award, the second Cy Young of his career.
In December 2010, MLB.com talked to Halladay about one of his more unusual accomplishments: getting mentioned in a Christmas song. Canadian country singer Gord Bamford recorded a Christmas song in 2009 called "Baseball Glove," in which a boy longs for a glove with Halladay's autograph.
"It was surprising to say the least," Halladay said at the time.
Bamford co-wrote the song in the summer of 2009 with Byron Hill, who has written country hits like Alabama's "Born Country," George Strait's "Fool Hearted Memory," Gary Allan's "Nothing On But The Radio," and Joe Nichols' "Size Matters."
"I wanted to do a Christmas song because I had never done one," Bamford said. "But I wanted to do something a little bit different than a traditional Christmas song. So with my love of baseball, and at the time, the Toronto Blue Jays and Halladay, it just kind of fit in there."
Bamford released the song late in 2009, just before the Blue Jays traded Halladay to the Phillies.
"It's still a great song, but there went our marketing plan," Bamford said with a laugh. "But he's such a class act, so it's nice to see him go to a team with a chance of winning the World Series. It's nice to see him go to a contender."
Halladay never won a World Series with the Phillies, but he created many memories for Phillies fans.
Here are five of his most memorable moments in a Phillies uniform:
1. Making Postseason History (Oct. 6, 2010)
Halladay waited his entire life to pitch in the postseason, then pitched the game of a lifetime in Game 1 of the NLDS. He threw just the second no-hitter in postseason history in an unforgettable performance in front of an electric crowd at Citizens Bank Park.
"The longer you play, the more you think about having that chance and being able to be involved in it," Halladay said that night. "It's been fun to do here because of the atmosphere and the guys on the team. It's been really everything that I hope it would be. It's something that I've looked forward to, and obviously very glad I got the chance."
Said Brad Lidge: "You go back and you see pitches guys were throwing 50 years ago and they might have the old fastball and maybe something else, maybe a curveball. But I think 50 years from now, people are going to look back and say, 'Roy had everything then that we have now.' I don't think you could throw a lot more stuff that he's thrown."
2. The Perfect Game (May 29, 2010)
Halladay became the 20th pitcher in baseball history to throw a perfect game, carving up the Marlins in a 1-0 victory at Sun Life Stadium.
"It's something you never think about," Halladay said. "It's hard to explain. There's days where things just kind of click and things happen, and it's something you obviously never go out and try and do. But it's a great feeling."
3. Finally, October Baseball (Sept. 27, 2010)
Halladay shuts out the Nationals to clinch the Phillies' fourth consecutive division title and the best record in the league. Afterward, teammates waited for Halladay, Mike Sweeney and Brian Schneider to pop the first bottles of champagne. It was their first trip to the postseason after a combined 40 years and 2,767 regular-season games in the big leagues.
"It was the right thing to do," Ryan Howard said.
"We were first-timers," Halladay said with a smile.
4. Winning on One Leg (Oct. 21, 2010)
The Phillies faced elimination against the Giants in Game 5 of the NL Championship Series, then Halladay pulled his right groin muscle in the second inning at AT&T Park. Despite not being able to top 90 mph with his fastball, Halladay pitched six strong innings in a victory to send the series back to Philadelphia.
"I felt like it was something I could get by with," Halladay said.
"He wasn't going to let us take him out," Charlie Manuel said.
"After a couple innings, I was like, 'God, this guy is pitching on one leg. Really?'" Shane Victorino said. "His velocity wasn't 92, 93 [mph]. It was 89, 90. That shows me what he's about. He wasn't coming out of the game, I can tell you that much."
"He's a man," Jayson Werth said.
5. Falling Short (Oct. 7, 2011)
Halladay waived his no-trade clause to join the Phillies because he believed he could win a World Series in Philadelphia.
He fell short of that goal with Game 5 of the 2011 NLDS encapsulating his failed pursuit. Halladay allowed just one run in eight innings against the Cardinals at Citizens Bank Park, but St. Louis ace Chris Carpenter threw a shutout to clinch the series with a 1-0 victory.
Halladay sat at his locker for more than 20 minutes after the game before slowly removing his uniform for the final time.
He would never again pitch in the postseason.
"The hard part is you think about all the hard work you put in over the course of the year, all the anticipation, all the excitement," Halladay said. "You have two days leading up to the game today, knowing how big the game is going to be. All of a sudden that kind of dissipates. It's tough. It's hard to have it end like that. You always want to finish happy."
Halladay might not have finished happy like he had hoped, but he still provided Phillies fans plenty of good times over the years.