The former Manchester United and Republic of Ireland skipper is seeking payment of £200,000 that he claims is owed to him on foot of a confidentiality agreeement he agreed with Sunderland owner Ellis Short when he parted company withthe club.
Though Quinn has also since departed Sunderland, speculation is mounting that he could be called to give evidence when the case is heard by the Premier League managers' arbitration tribunal.
In a Sunday newspaper report Keane's lawyer, Michael Kennedy, confirmed that a case was pending involving his client.
A statement issued by Sunderland said: "Club officials are quite bemused that proceedings have been issued at the managers' arbitration tribunal and will vigorously defend Sunderland AFC's position in this matter."
Keane left Sunderland in December 2008 and it is widely accepted that towards the end of his time there his relationship had deteriorated significantly with Short.
The Texan billionaire is said to have disliked the fact that Keane didn't reside in the north-east while in charge of the club.
Keane had initially operated under the Drumaville consortium of Irish businessmen.
It is thought that, on the basis of a confidentiality clause, the club agreed to pay Keane a sum of money when he departed.
It is believed that Sunderland haven't paid this money, allegedly citing a newspaper interview given by Keane two months after he left the job.
Source: Sunderland-Mad
Source: FOOTYMAD
