Diego Costa and Oscar allegedly came close to blows during a Chelsea training session at Cobham this morning.
According to The Mirror, the problems started when Oscar went in on Costa with "a particularly hefty tackle".
Costa is then said to have "responded in kind with an even stronger challenge", prompting Oscar to square up to his compatriot. The pair allegedly exchanged angry words and had to be pulled apart by teammates and coaches.
A source told the newspaper that tensions soon dissipated, however, and the duo were seen heading towards the changing rooms together at the end of the session.
The Blues are preparing for an FA Cup tie with third-tier side Scunthorpe United this weekend.
