Football: City violence mars match joy.
Violence flared as a surge of Man City fans bore down on police lines following the Riverside visitors' only goal.
Chairs were ripped out and hurled at police - several officers were struck in the face.
Officers drew their truncheons and reinforcements were called in. Seven Manchester City fans arrested.
In the melee one visiting fan appeared to grab an officer by the ear while others appeared to menace police with clenched fists.
Cleveland Police said the violence flared after one away fan removed a 4ft-long metal safety barrier blocking access to the pitch.
Boro boss Gareth Southgate said: "I've never seen any trouble at our ground so it's a shame we've had some problems at the end because this has always been a very safe environment in which to come and watch football."
The worst crowd violence seen at the Riverside threatened to disrupt the celebration of Boro's 8-1 victory.
Earlier, City fans waving inflatable bananas seemed to be taking the thrashing with good humour and their protest was confined to calls for Sven Goran Erickson to keep his job - until the last five minutes of the game.
But with just minutes to go, waves of City fans began jumping over barriers to reach the front of the stands to confront a double line of police and stewards.
The crush at the front of the away stand looked like spilling over onto the field, but police managed to contain the angry fans.
The uproar held up the celebratory lap of the pitch by players and their children as they were told to clear the field for their own safety.
Match commander Superintendent Martin Campbell, said: "It appears that towards the end of the game a visiting fan removed a 4ft-long metal safety barrier which is in place to prevent access to the pitch.
"Fearing that it could be used as a weapon or to gain access onto the playing area, an officer removed this barrier and a skirmish then took place, spreading into other areas of the crowd".
Police reinforcements were immediately called into the ground.
"I would like to praise the match referee who did an excellent job; it seems he was fully aware of the unfolding events and he ensured that players were swiftly removed from the pitch at the end of the game."
He praised the home fans saying: "They were extremely well-natured and I'd like to praise them too.
"It is a shame that such a fantastic end to the season and what was always intended to be a great family occasion was marred by the behaviour of a small minority."
VIOLENCE: Manchester City fans clash with police near the end of the match, above