Bako underwent a battery of tests after the game and apparently showed no signs of a concussion, but Perlozzo elected to start third-string backstop Alberto Castillo on Tuesday. That way, the Orioles can make sure their backup catcher is as healthy as possible, especially with starter Ramon Hernandez nursing a strained left oblique.
"There was some concern that he had a possible concussion, although the doctor didn't see that. But supposedly when you take a blow like that, if you take another one in the next 48 hours, it can cause some other problems," Perlozzo said. "He was probably going to catch two of three anyway, and Castillo has caught Daniel [Cabrera] in winter ball, so I thought it was the time to err on the side of caution and let Bako come back tomorrow.
"But I don't have any problems with putting him in the game tonight."
Bako, for his part, said he felt much better Tuesday than he did Monday night. The veteran had trouble explaining his exact symptoms, saying that he didn't have a headache or excessive dizziness, but that he did feel a little woozy. Bako also said he was capable of playing Tuesday night and had no doubts about his condition.
Perlozzo, meanwhile, was impressed by the grit his catcher showed. Bako caught four innings after the collision and struck out looking in the seventh inning before telling Perlozzo that he wasn't comfortable swinging again.
"He's been a gamer from the day he walked into camp," Perlozzo said. "I think he's a big upgrade on what we've had in the past, and another one of the guys on our ballclub that I think is a good baseball guy. And he's a team guy."
Back in action: John Parrish made his first appearance of the season on Opening Day, but the significance of his outing went back a few seasons. The southpaw hadn't pitched in the big leagues since June of the 2005 season, and he spent all of '06 recovering from multiple surgeries on his pitching elbow.
Parrish got five outs Monday night and didn't allow any hits, but his relief went beyond the box score.
"It's been almost two years, so it's going pretty smooth as long as I keep taking my time and not rushing myself," he said. "The main thing is that I wanted to get in and throw strikes and minimize the damage as much as possible."
"He hasn't been in the big leagues for a little while and he came in in a clutch situation," added Perlozzo. "He stayed within himself and he pitched. That's kind of what we were hoping we'd see. You see how he did in the spring, but when the bell rings you are hoping for him to maintain that composure and pitch.
"And he did. I think he's going to be a good pitcher for us this year."
Parrish said he didn't feel much in the way of nerves and that he's fine with whatever role the Orioles choose for him. For now, he's the second situational southpaw and a reliever who will see work early in the game. Parrish said that the time away from competition may have helped him in some respects, most of them psychological.
"I feel more in control, more confident in the work I'm going to get," he said. "As long as I keep throwing strikes and maintaining that same strike zone in and out, then I'll throw in more games."
Bumps and bruises: Hernandez elected to skip batting practice Tuesday and maybe held out of the lineup a little longer than expected. The backstop was hoping to make his season debut against the Yankees this weekend, but if he can't swing in the next few days, the Orioles may do without his services until they return home.
"Obviously, you have some concern about it or otherwise, he'd be in there playing," Perlozzo said. "My biggest concern is we don't want something to happen that is going to be long-term. That's our major concern. It's early in the season. ... We're going to hope that he is 100 percent before we feel comfortable to put him back in there."
Baltimore's other prominent injury is to left fielder Jay Payton, who's been sidelined with a strained left hamstring. Payton is eligible to come off the disabled list April 11, and Perlozzo is hoping to see him as close to that date as possible. Still, he wouldn't discount the possibility that Payton may need to play a rehab game or two.
"I don't know that I'd say expect [him to be back]. We're certainly hoping that's the case," he said. "I think [Baltimore trainer] Richie [Bancells] told me that they were going to try to start running him in New York, so we'll have a lot better idea. And that's assuming the weather's OK, and everything like that."
Coming up: The Orioles and Twins will meet for a series finale Wednesday, a game that pits Jaret Wright against Minnesota's Ramon Ortiz. Both Wright and Ortiz will be making their first start for their respective teams.
Quotable: "He got away from pitching like he'd been doing all spring. And what the heck? He was an Opening Day starter for the first time in his life and he probably wanted to do well. I think he just went to muscling a little bit more instead of pitching. He'll be fine. He's the least of my concerns." -- Perlozzo, on Erik Bedard's first start