Altidore, who had just come back from a hamstring injury when he went to the Gold Cup, was released from his national team this week along with Greg Garza and Alfredo Morales. U.S. coach Juergen Klinsmann called up Alan Gordon, DaMarcus Beasley and Joe Corona in their place for the CONCACAF championship knockout rounds.
"Jozy never really got into this tournament and never really picked up the rhythm," Klinsmann said this week. "He's just simply not in the shape right now to help us. For Jozy it’s just simply going back to Toronto, picking up his rhythm, getting in shape, working on his fitness and then he will start scoring goals again."
That may lead some to wonder why Klinsmann bothered to summon Altidore in the first place.
An unfazed Altidore, who estimated his health at 80-something per cent, said he was not unsurprised that he came home early given his injury comeback.
"Because I wasn't where I needed to be," he said. "The window was too small to get to where he (Klinsmann) wanted me to get."
"I'm happy to be back here," he added. "I missed Toronto ... I look forward to playing Saturday."
Toronto coach Greg Vanney says the team has tested Altidore's fitness ahead of the visit by the Philadelphia Union.
"I don't know if he's 100 per cent but he feels he can play. He feels good about where's he's at, knowing he has some more space to gain. But at the same time, part of that he's going to get by playing games ... We'll get him to where he needs to be."
Toronto captain Michael Bradley remains with the U.S. team.
Toronto (7-7-3) also gets Canadians Ashtone Morgan and Jonathan Osorio back from national team duty.
Toronto is without goalkeeper Chris Konopka, suspended one game after taking down a New York City FC player last week. Joe Bendik, last year's starter who lost the No. 1 job when he was hurt six games into the season, takes over. Defender Nick Hagglund is also out after having his appendix removed.
On the plus side, Damien Perquis appears to have recovered from a knee knock while fellow defender Clement Simonin is back from a knee surgery.
Philadelphia (6-10-4) will be without captain Maurice Edu, who started his pro career with Toronto, due to yellow card accumulation.
The game is matchup of the two worst defences statistically in Major League Soccer.
Philadelphia ranks 20th in the league, conceding 1.60 goals a game. Toronto, which has yielded eight goals in its last two games, isn't much better at 19th and 1.59.
"We've given up way too many goals in the first 15 and first 30 minutes of games. A big part of that is concentration," said Vanney.
After a rocky 1-7-3 start, Philadelphia is back on track. It has gone 5-1-1 in its last seven matches in all competitions.
Both teams are caught up in a logjam in the East standings. Toronto, one of three teams on 24 points, stood fourth going into the weekend while Philadelphia, on 22, was seventh.
Only six points separated teams two through nine in the East. The top five make the playoffs.
Toronto won 1-0 on a Sebastian Giovinco free kick when the teams met May 2 at PPL Park.
Giovinco is coming off his third player of the week award in the wake of his hat trick in last week's 4-4 draw with New York City FC.
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