Both are back in their home country for medical attention and will miss the MLS club's end-of-season player availability Tuesday.
Toronto general manager Tim Bezbatchenko said Defoe left for England on Sunday in order to meet a German specialist about his nagging groin injury. If surgery is required, the decision will be made over the next couple of days in consultation with the club.
Bezbatchenko said there was a time element in that the specialist was only in London for a specific period of time.
"He needed to get over and get on that person's schedule, which required him to leave," he said in an interview.
Bradley, meanwhile, is in New York for a procedure to correct a season-long nerve issue with his foot. The 27-year-old U.S. international has played through pain this season.
"They want to do it as soon as they possibly can so they can get back on the pitch," Bezbatchenko said of Bradley and Defoe.
While Toronto's season is over, the players continue to train in town this week with exit meetings planned for the end of the week and early next week.
Bradley is expected back by then. Bezbatchenko said the conversation with Defoe will either take place in person or via phone.
"This happened last year with a couple (of) players," he said. "Sometimes you have to have a phone conversation because that's just life."
Toronto turned down a club-record bid for the English striker at the end of the summer transfer window, leading to speculation that he might leave when the next window opens in January.
"At this point, he's still a TFC player," said Bezbatchenko. "We need to first get over his injury, then we'll sit down and talk to the player and figure out what his desires and goals are and see if they match with our club.
"Obviously we only want players that want to be here. Jermain's never said he hasn't wanted to be here. So until that happens, Jermain is here and we want him to be here. Because he's proven to be a prolific scorer in this league and after you have one year under your belt, we've seen other players come back and do even more damage in the second year. Until otherwise, that's going to be our plan."
The first public clue that Defoe was back home came via Twitter from a mobile hair extensionist in England.
"Look who I bumped into @IAmJermainDefoe at my local tesco," tweeted @ExtensionsLeona in posting a photo of a smiling Defoe posing outside her car window at a supermarket.
Defoe also returned home in the summer for medical treatment.
Defoe, 32, led Toronto with 11 goals in 19 games and TFC never lost (6-0-2) a game in which he scored. But he did not score in the last half of the season, missing 11 of 17 outings through injury and one through suspension.
Defoe saw just 360 minutes playing time spread over six games during the second half of the season.
Speaking to Toronto reporters last Thursday, he complained of being unable to turn sharply or shoot properly because of the groin injury.
"It's something that I need fixing, because it's stopping me from what I really want to do in games,'' he said.
Defoe also was upset that some have questioned both his commitment to the club and whether he is really injured.
He repeated he has never said publicly that he wants to leave a club. But he has stopped short of saying he will be back in Toronto next season.
"At the end of the day, I don't know what the future holds,'' he said. "But what I would say is that I was desperate to get into the playoffs. It's something I would love to experience.''
Toronto (11-15-8) missed the post-season for the eighth straight year.
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