Boller got the first start, completing 11 of 15 passes for 102 yards. However, the former first-round draft pick also had a fumble and an interception.
"There are a few plays I wish I could take back," said Boller, who also had two passes dropped.
Smith wasn't exactly sterling, either. He completed five of 12 passes for 74 yards, but he did connect with Darnerien McCants and Justin Harper for 30 and 18 yards, respectively, to finish with a 62.5 rating.
"I thought Troy was poised," Harbaugh said. "He threw some NFL balls in there. That ball across the middle in the fourth quarter was a heck of a throw. He scrambled around and did a nice job."
Now, Smith is looking to build upon that showing and two rookie starts last season where he threw two touchdowns with no interceptions in 76 throws. Smith acknowledged that this upcoming game is "vital" for him.
"It's very, very important for myself and my development for the team," Smith said.
"I haven't stepped into the situation any day in practice, saying my performance will help me or not help me," Smith said. "I try to approach this the same way."
Meanwhile, rookie quarterback Joe Flacco received a rude greeting in his first NFL game. The first-round draft pick went 0-for-3 with a lost fumble and was sacked twice. Despite the rough start, his confidence wasn't shaken.
"It was a good learning experience," said Flacco, who was drafted 18th overall. "I have to do a better job of protecting the ball. I pride myself on staying calm. It was obviously a little bit different from what I'm used, but that's what the game is all about."
Copyright 2008 by The Associated Press