The Premier League has confirmed it will look into Everton goalkeeper Tim Howard's absence from the match against Manchester United last month.
The American keeper was omitted from the Toffees' squad for the match at Goodison Park on April 28.
However, as Howard made his initial loan move from United into a permanent transfer in February, it is claimed there was no reason why he could not have faced his former club.
"We will be contacting both clubs as a matter of urgency to find out what has gone on," Premier League spokesman Dan Johnson told the News of the World.
"As Howard's is a permanent transfer there is no reason why he could not have played against Manchester United.
"Had such a clause been included in the transfer we would not have allowed it - it would have been a clear case of third-party interference.
"We certainly have no record of an agreement between Everton and United that Howard could not play on April 28."