He turned up with a bang once the game began.
Puig hammered a two-run homer in the first inning off Clayton Kershaw, who was making his season debut for the Dodgers.
Puig was greeted with a mix of boos and cheers as he rounded the bases to put the Reds ahead 2-0.
The Dodgers honored Puig, Matt Kemp, Alex Wood and Kyle Farmer in a pregame video that highlighted their time in LA. Puig, Kemp and Farmer doffed their caps in appreciation. Wood just rejoined the Reds after being injured.
Puig, from Cuba, awed fans with his cannon of an arm and infuriated management with his inconsistent efforts on the field during his six years with the Dodgers.
He missed receiving his National League Championship Series ring in person from Dodgers owner Mark Walter and other front-office personnel.
They presented the jewelry to Kemp, Wood and Farmer during an informal gathering outside the visitors' clubhouse.
"Just the six of us sharing some stories, saying hello and more so us thanking them for what they did to help us accomplish what we accomplished last year and wishing them well," Dodgers manager Dave Roberts said.
Asked about missing the gathering, Puig said, "He can send the ring to my locker or give it to me at batting practice. He can give it to me in person, I don't care."
Roberts chuckled when asked if he was happy to be on the other team now when Puig's name comes up.
"Yeah, I am happy," he said, smiling.
Roberts said he and Puig "are good," and they've been in touch via text message and a phone call during spring training.
"This guy did a lot of things in the community and helped the Dodgers do a lot of good things," the manager said. "When he's motivated and incentivized, he's a very good player."
Puig was popular with Dodgers fans for his colorful personality, home-run trots and ability to throw out runners from right field. He made headlines away from the field when his Los Angeles home was burglarized multiple times.
At the ballpark, he was benched at times and the team considered trading him long before it did because of his perceived lack of hustle or interest in following orders.
On Monday, Puig showed up 70 minutes late to a scheduled news conference with local media.
He took questions in English and Spanish for several minutes when Dodgers closer Kenley Jansen suddenly appeared from behind a wall of TV cameras to greet Puig with a hug.
"Papi," Puig said as the former teammates embraced.
Reds manager David Bell said Puig has "absolutely" been punctual with his new team.
"But that wouldn't be the first thing I would talk about," he said. "It would be more about the way he has played the game and the teammate he has been. He has been outstanding. We love having him here."
Puig was part of a seven-player deal with Cincinnati in December that included Kemp, Wood and Farmer.
He batted third, just ahead of Kemp, in the opener of the three-game series.
Turner Ward, the former Dodgers hitting coach who is employed in the same role for the Reds, was working in the batting cage when Walter, president of baseball operations Andrew Friedman, team president Stan Kasten and Roberts walked over to the visitors' clubhouse to present the rings.
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