The Ravens trampled the Dolphins, scoring 24 unanswered points in a 27-10 triumph on Saturday at Hard Rock Stadium in Miami. Jackson completed 7-of-10 passes for 98 yards and a score in the win. He also ran for 39 yards and another score.
"I think today was his breaking out in a game," Harbaugh said. "We've seen it in practice where he's done some really good things, but we hadn't really seen it in a game yet. And today just fell into place for him a little bit. I thought [offensive coordinator] Marty [Mornhinweg] did really nice job with the play calling, but he handled himself well. He got to the line of scrimmage, he made calls, he made checks, made adjustments. Didn't have too many formation issues."
Harbaugh also credited the rookie for the offense not having any false starts in the second half.
Jackson has completed 25-for-53 passes for 299 yards, three touchdowns and one interception in four preseason games. He also has 111 yards and two scores on 20 rushing attempts.
"I started off a lot slower last week. It wasn't last week, it was actually this week on Monday," Jackson said. "Today, I just came out a little faster."
Robert Griffin III started the game and played the entire first half. He completed 9-of-15 passes for 66 yards, while rushing for 41 yards on five carries.
Jackson sits behind Joe Flacco at the quarterback slot on the Ravens' unofficial depth chart. Griffin is listed as a third-string option. Despite the crowded quarterbacks room, Griffin said he doesn't feel pressure when it comes to the team deciding to keep two or three quarterbacks on the roster.
"No, there's no pressure," Griffin said. "I should say there is no pressure that I'm going to apply to myself to go out and perform like I have been and I know how, and the coaches have taught me within the system. I know the team we'll be facing is my former team that I played for and was drafted by."
"There will probably be a story line around that. But aside from that, it's just go out, play ball and have fun, and continue to do what we've been doing, and let the coaches make the decisions at the end of the day."
The Ravens host Griffin's former team -- the Washington Redskins -- in their final preseason game at 7:30 p.m. Thursday at M&T Bank Stadium in Baltimore.
"Obviously, Robert handled himself very well, and our young players played well in the first half," Harbaugh said. "Probably should have been tied. So that was a starting point, was a good plus."
"In the second half, Lamar came out there with his guys, and I thought it was just impressive to see. Moving a lot of no-huddle. Got the hurry-up offense. Just the conditioning ... Down here it's a little bit hotter, it's a little bit humid, and I thought our conditioning paid off very well. Guys executed when they were tired and made plays. Lamar made plays, of course, and moved the chains and scored some points."