Kemp doubled over in a half-smile, half-grimace and whispered something to Blake, who laughed.
In an off-season in which owner Frank McCourt's divorce proceedings dominated the Dodgers-related headlines, Kemp was the one player who managed to remain in the spotlight.
Actually, if anything, the spotlight on Kemp intensified.
And it was because of something that had nothing to do with baseball: He was photographed at a Mexican resort with Rihanna.
His relationship with his "friend," as he calls the Grammy-winning R&B singer -- his "girlfriend," according to the tabloids -- has turned Kemp into a minor Hollywood celebrity.
His image appeared in gossip magazines. He was featured on TMZ.
"It was," he said, "a little overwhelming."
The newfound notoriety not only armed teammates like Blake with fresh material for good-natured teasing but also led to some unusual media requests. The Source magazine, the self-proclaimed "Bible of Hip-Hop," wants to interview him. GQ has scheduled a photo shoot with him.
He seems puzzled by the attention.
"I've never seen a baseball preview in the Source magazine," he said, laughing. "I don't consider myself a model of no type."
But Kemp said the extra attention hasn't diminished the drive that transformed him over the last few years from a talented but clueless prospect to a Gold Glove and Silver Slugger winner.
"I guess you get used to it," he said of his new fame. "I don't worry about it now. It's not affecting my work."
Today is the day position players have to report for camp, but Kemp has been here since Monday.
While most of the returning Dodgers said it took them anywhere from a couple of days to a couple of weeks to emotionally recover from failing to beat the Philadelphia Phillies in the National League Championship Series, Kemp said the pain stayed with him through the winter.
"The last two years, it hurt," Kemp said. "It hurt me. I wanted to win. It's not fun to get eliminated. I don't think I'm going to get over it until the first time we win it."
Kemp said he spent the winter working out in Los Angeles and, against the advice of his agent, former All-Star pitcher Dave Stewart, took less than two weeks off after the season before beginning his training program.
"It's hard to just sit around and do nothing, man," Kemp said. "I don't like sitting around. I have to get up and do stuff."
He spent the two weeks leading up to spring training working out in Dallas with Torii Hunter and Gary Sheffield.
He slept at Hunter's house and saw the Angels center fielder's trophy case, which included nine Gold Gloves.
Kemp won his first Gold Glove last season, his first as the Dodgers' everyday center fielder.
"I'm going to try to get mine," Kemp said. "I'm not going to try -- I am. He has to stop playing, though, so I can catch him."
Kemp said he has written down his season goals in a journal he has kept for the last four years.
But no details?
"I can't tell you the goals," he said. "They won't come true."
Expectations, though, are high thanks to last season, when he hit .297, had 26 home runs, 34 stolen bases and 101 runs batted in -- prompting talk that he could one day be a 40-40 man: 40 home runs and 40 stolen bases.
Manager Joe Torre said Kemp hasn't done anything to indicate his focus is waning either. And while Torre also said he's talked to Kemp about off-the-field issues, the conversations weren't serious.
"Matt Kemp, last year, probably came further than anybody," Torre said. "He was enormously improved last year. Just knowing his personality, I don't think he's going to be satisfied with that."
General Manager Ned Colletti recalled the time Kemp went to play ball in the Dominican Republic in the winter of 2006-07.
"He went down there and he struggled," Colletti said. "But you know what he did? He stayed. He fought through it. It's a tough place to play. He didn't speak the language. Someone with less intestinal fortitude would have come home early.
"I think that experience helped him."
Kemp became a millionaire this winter, rewarded with a two-year, $10.95-million contract.
Yet dealing with present-day matters was only part of Kemp's changed reality; he had to deal with his past too.
Among the incidents that surfaced and were widely reported in gossip publications was that Kemp had a restraining order filed against him by an ex-girlfriend in 2008.
"As you can see with the restraining order, it was dropped," Kemp said. "I've never, ever did anything to harm anybody in my life, especially a woman. It hurts my feelings."
Kemp said he has learned that he has to be careful with what he does or where he goes.
"I've been here for four years," he said. "I know what L.A.'s like. It's not like a normal city. It's a big city. It's Hollywood -- entertainment capital of the world. It's not just a normal baseball city."
But in the first week of camp, a couple of Dodgers officials didn't seem pleased to learn there was a risque video on TMZ.com that showed Rihanna at a birthday party that Kemp reportedly threw for her in Arizona.
Kemp said he doesn't anticipate the scrutiny to become significantly worse.
"I haven't seen too many people popping out of bushes," he said.
Whatever happens, he wanted to make one point clear.
"I'm not a celebrity," he said. "I'm a baseball player, man."