Samuel Eto'o faces stiff competition from Italy under-21 forward Mario Balotelli for a starting place when leaders Inter Milan face Genoa at home on Sunday.
The Cameroon striker's struggles with his form mean he is no longer guaranteed a start while Balotelli's impressive recent showings have sparked a media campaign for Marcello Lippi to call him up to Italy's senior team for the World Cup.
Eto'o is still favourite over Balotelli to partner Diego Milito in attack this weekend, although Friday's La Gazzetta dello Sport put the probability at just 55-45 percent in his favour.
David Beckham could be used in Milan's attacking trident to cover for Pato, who has a thigh strain, as former Roma winger Mancini is not fit either.
Pato may be back for Wednesday's Champions League last-16 second leg at Manchester United, when Milan need to reverse a 3-2 deficit.
"I'm (training) with the squad, so I can say that I'm okay and I've recovered," Toni, who joined Roma in the transfer window after falling out of favour at Bayern Munich, told reporters.
"There are two-and-a-half months to get back to form and I hope to be at the World Cup."
Italy striker Vincenzo Iaquinta is expected to return to Juventus's squad for Saturday's visit to Fiorentina after finally recovering from knee surgery in October.
