"Abhorrent. Well done @JackGrealish1 for keeping his cool," Gary Lineker tweeted.

Former Villa forward Marlon Harewood was another who applauded Grealish for his restraint, posting: "What an absolute disgrace! What an idiot! Well done Jack Grealish for not reacting to such a disgusting act!"

Meanwhile, former Liverpool player Luis Garcia acknowledged the example the England under-21 player set for children watching.

"Well done Jack Grealish. Many kids are watching and players have to behave. After that situation not easy to stay calm," he wrote.

Stoke City midfielder Charlie Adam responded to the incident by expressing his concern for the safety of the players.

In a game between Rangers and Hibernian on Friday, Gers captain James Tavernier found himself face to face with a fan who had leapt from the East Stand to confront him.

Bournemouth's Harry Arter, meanwhile, tweeted that he hoped to see Grealish score the winner after the incident, and he was not to be disappointed, the 23-year-old scoring the game's only goal in the second half.

Birmingham condemned the attack as "deplorable and disgusting" and Press Association Sport understands the club will apologise to Grealish personally.

It is also believed the Blues will take the strongest possible action and ban the man for life from St Andrew's.

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