MANCHESTER, England (AP):

Mario Balotelli's volatile relationship with Manchester City manager Roberto Mancini appeared to escalate yesterday when the two men were photographed in a heated altercation during training.

Mancini shouted at the Italy striker and grabbed his training bib before the pair were separated.

The incident occurred after a tackle by Balotelli on a teammate, according to online news reports accompanying the photographs.

The training session was closed to the media but City's training pitches are viewable from public walkways. Exactly two years ago, a brawl between Kolo Toure and Emmanuel Adebayor was photographed on the same pitches.

Yesterday's altercation is the latest chapter in Balotelli's turbulent City career and overshadowed the club's preparations for an FA Cup third-round match against Watford tomorrow.

Mancini has become increasingly frustrated with Balotelli, as the 22-year-old player's form has dipped this season.

But Mancini has insisted that his compatriot will not be sold in the January transfer window, saying earlier this week that the club's Abu Dhabi owner is a fan of the striker despite a series of disciplinary violations that led to Balotelli being fined two weeks' wages.