Jonny Evans has apologised to Stuart Holden for the challenge which will rule the Bolton midfielder out for up to six months, emphasising it was not deliberate.
Holden, 25, needed 26 stitches in a gash in his knee and was heading to London for surgery. Manchester United defender Evans was sent off as his side went on to record a 1-0 victory at Old Trafford.
Bolton boss Owen Coyle refused to condemn the Northern Ireland international after the game and Holden revealed on his Twitter account Evans had apologised to him on the phone. He said: "Just had sincere phone call from Jonny Evans wishing me best in recovery, def (sic) wasn't intentional just unfortunate part of game."
It means the USA international will take no further part in the season, including the FA Cup semi-final against Stoke at Wembley on April 17.
Holden thanked fans for their support and added: "I can promise you I will come back stronger and better than before. Have had back luck in the past and will continue to beat it."
Coyle is now focussed on nursing the Aberdeen-born player back to full fitness.
He said: "First and foremost our main concern is Stuart and his recovery. He will get all the time and support he needs.
"Stuart has been outstanding this season and has shown he is one of the best midfielders in the Barclays Premier League. He has such desire, strength of character and a winning mentality he will draw on those attributes in his rehabilitation."
Holden, who arrived at the Rebok Stadium in Janauary 2010 after a successful spell with MLS side Houston Dynamo, has been unlucky with injuries.
Now he will watch the rest of the season unfold from the touchline, while he is also ruled of the USA's Gold Cup campaign in June.
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