Summary:
Referee Michael Oliver was left red-faced after being confronted by England's No 1 in the first half of Manchester United's 1-0 win over Manchester City.

Full article:
Manchester City and England goalkeeper Joe Hart was fortunate to escape unpunished after he appeared to square up to the referee during the Manchester derby. Hart was incensed after Chris Smalling blocked him from releasing the ball in the 30th minute of the game. And, despite Smalling being shown a yellow card -  the first of two he received before half time - Hart was furious. VIDEOS Scroll down to watch Sportsmail's Big Match Stats from the Manchester derby . Joe Hart approaches Michael Oliver near the half-way line after being incensed by Smalling's block on him . The England goalkeeper inclines his head towards the official, who tells him to return to his goal . The England No 1 sprinted towards Oliver to remonstrate, before squaring up to the official. Pictures seem to suggest that Hart's head may even have made contact with the referee, which could see him in trouble with the FA. However, Oliver seemed to brush off the encounter, booking Smalling and sending Hart back to his goal before allowing the game to continue. Hart certainly appears to make contact with the referee, but Oliver appeared unpeturbed . Hart had been angry after Chris Smalling attempted to block his clearance, for which the defender was booked .