Manchester United winger Nani was unhurt after his Bentley Continental collided with an unmarked police car.
The officer has since been suspended from driving duties.
A spokesman for Greater Manchester Police said: "At about 6.40pm on Friday 15 February 2013, an unmarked police car responding to an emergency call was travelling along Gatley road at the junction with Kingsway, Stockport.
"As the police car entered the junction it collided with a Bentley Continental. The passenger in the police car received minor injuries and only minor damage was caused to both vehicles.
"The police driver has been suspended from driving duties in line with normal procedure."