Working in short sleeves on a cold, gray afternoon, Imanaga struck out nine in Chicago's home opener. The Japanese left-hander, who signed a $53 million, four-year contract with the Cubs in January, allowed two singles and walked none.
"This is probably my 10th straight opening day so it's always fun to go," fan Chris White said. "It's always a blast no matter what the weather is. Just always worth coming here and the atmosphere is always incredible no matter what time of year it is."
Yak-Zies held its annual WXRT radio opening day party, which they've held there for more than 30 years.
"It's tradition. It's the best day of the year. There's hope. You never know what's gonna happen in the season but this is the happiest day of the year," said Leah Spagnoli, fan.
Dakota Hudson also was impressive in his first start for Colorado, but a pair of errors on Jones on one play in the sixth sent the right-hander to the loss.
With one out and runners on first and second in a scoreless game, Christopher Morel lined a single into left field. The ball went under the glove of a charging Jones and rolled all the way to the wall.
Ian Happ and Seiya Suzuki raced home as the Wrigley Field crowd of 40,072 roared its approval. Jones' throw from the warning track got away from second baseman Brendan Rodgers in the outfield grass, and Morel scored on a headfirst slide.
Jones also dropped a routine fly ball during Sunday's 5-1 loss at Arizona, leading to two unearned runs.
Cody Bellinger added a two-run single in the seventh as Chicago earned its second straight win after dropping the first two games of the season at Texas.
Hudson (0-1) was charged with three unearned runs and four hits in 5 1/3 innings. He agreed to a one-year deal with Colorado in free agency.
Yency Almonte worked the seventh for Chicago before Drew Smyly finished the three-hitter.
Imanaga (1-0) was working on a no-hitter before Charlie Blackmon singled to center with two out in the sixth inning. Rodgers followed with another base hit, but Imanaga escaped the jam by fanning Jones.
Colorado got its first baserunner when Kris Bryant reached on third baseman Morel's error in the second. But Ryan McMahon and Elias Díaz struck out swinging before Ezequiel Tovar flied out, ending the inning.
The home opener marked the first Wrigley Field appearance for new Cubs manager Craig Counsell, who got a warm greeting from fans and players. The club has high hopes for him and the team they have built around him.
"I think he's the best in the business. We're fortunate to have him," said Cubs co-owner Laura Ricketts.
Cubs Hall of Fame 2nd baseman Ryne Sanburg joined other legends on the field to throw out the first pitch.
"I know they're gonna play the game the right way with Counsell at the helm. I'm looking forward to the season," he said.
With a new baseball season comes more changes at Wrigley, too.
"We are always changing Wrigley Field," Cubs president of business operations Crane Kenney said. "We're always working to keep it up to speed and this year we replaced our wood roof, which goes back to the 19 teens."
Plus, new outside lighting and signs on the Wrigley Rooftop buildings.
Also new this year is team manager, Craig Counsell.
"Craig has been great," Cubs VP of Community Affairs Julian Green said. "I had a chance to spend some time with him down in spring training. He has a clubhouse stoked up, it's really cool. I think we've got one of the best managers in baseball."
The Cubs are offering special giveaways this season for fans.
"The first 10,000 early arriving fans will get a schedule magnet that they can't forget when Cub games are coming," Jen Martindale, Cubs senior vice president of marketing, said. "And we'll roll right into this weekend where we're going to be celebrating legendary radio broadcast her Pat Hughes with a sweater giveaway."
And plenty of special ticket offerings for those in the military, educators and medical professionals.
And how could we forget the food? The food options really stepped up this year, with a variety of nachos, burgers, and desserts to fuel you through the game.
The Associated Press contributed to this report.