The pair clashed on the pitch before half-time when Shawcross appeared to grab Van Persie around the neck, says the Daily Star. The Stoke star then barged into Van Persie as he left for the interval and they could be seen having a heated exchange as they headed down the tunnel.
Now it has emerged the duo continued their feud after the final whistle. It is understood there was another altercation outside the dressing rooms when Van Persie muttered something under his breath to Shawcross as the centreback was giving an interview.
Shawcross took offence but Van Persie, who scored in United's thrilling win, ignored him and walked off.
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