Johnson, 31, who signed a one-year contract with the Cubs shortly after noon CT, started in center field on Tuesday against the Giants and went 2-for-5. He had been released by the Toronto Blue Jays over the weekend.
"You guys don't know how happy I am to be here," Johnson said.
"He's a scrappy player and has good Major League experience and plays all three outfield positions and gives us some really nice depth," Cubs manager Lou Piniella said of the right-handed hitter. "He's a good person, good team guy in the clubhouse."
Johnson is a career .281 hitter, and has a lifetime .308 average against left-handed pitching. He won't exactly platoon with Felix Pie, but the Cubs did not have a viable backup in center.
"We've been working on right-handed outfield guys, and all of a sudden the best guy kind of falls in our lap," Cubs general manager Jim Hendry said of Johnson, who signed a one-year, $1.3 million deal. "He's a really hard-nosed player and a good hitter against left-handed pitching. He can play all three spots."
Against the Giants, Johnson struck out in his first at-bat in the first, and grounded into a fielder's choice in the third. With one out in the fifth, Johnson doubled off the wall in left, and reached third on an error by Fred Lewis before scoring on Derrek Lee's home run. He also grounded out in the seventh, then singled in the ninth and stole second before scoring.
He was eager to sign with the Cubs when he realized there wasn't room on the Blue Jays roster.
"I've always thought if Boston wins the World Series, and then the White Sox win the World Series, this is one of the only teams left that hasn't done it," Johnson said. "I've always thought, even since I started playing baseball, to be a part of something like that, there's nothing else I'd rather want. This was my first choice, and my only choice."
He does have a little history with the Cubs. On June 15, 2003, Johnson hit a walk-off homer in the 10th inning off Mark Guthrie to lift Toronto to a 5-4 Interleague victory over Chicago. It was his second homer of the game. He also connected off Kerry Wood in that series.
"People ask me what one of my memorable moments is and I think that's one of my memorable moments, being able to help your team with a walk-off homer," Johnson said.
The Blue Jays had signed outfielder Shannon Stewart this offseason, and Johnson became the odd man out. Was he surprised to be released?
"I was a little surprised," Johnson said. "We all knew it was coming, and it just happened to be me."
He missed more than three months last season after surgery on April 17 to correct a herniated disc in his lower back, and batted .236 in 79 games. His back is fine now.
"It's not a problem," he said. "That's where a lot of the 'surprise' comes from. I feel like I came into Spring Training healthier than ever. I was able to get that explosion back in my leg, which I lacked last year. To get the strength back and explosion back was a key for me in the offseason."
Piniella has seen Johnson play while in the American League with Tampa Bay. Cubs scouting director Tim Wilken was with the Blue Jays in 1999, and drafted the outfielder in the 17th round in the First-Year Player Draft. Johnson also was a teammate of Cubs pitcher Ted Lilly and a workout buddy with Ryan Dempster. He should benefit by being in the National League with all the double switches.
"He's had success hitting in the top part of the lineup," Piniella said. "We'll give him some at-bats and get him ready."
Sharing playing time isn't a problem, Johnson said.
"I worried about that last year," he said. "I had expectations of playing. I think if I go out there and play hard and try to have good at-bats and try to improve my swing and my defense on an everyday basis, the rest will take care of itself."
As for the rest of the Cubs bench, the extra players still in camp include Daryle Ward, Henry Blanco, Mike Fontenot, Matt Murton, Ronny Cedeno, and Alex Cintron.
"We've got some decisions to make," Piniella said.
There is the matter of Johnson's facial hair. It's an extended goatee, and Johnson apparently is well versed in Cubs' lore.
"Hopefully the goat is back," Johnson said. "Hopefully, the curse is gone. We'll see how it goes. If things are going well, it'll stay. If things go south, you'll see some facial hair changes throughout the year."
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.