Mark Wilson has committed his future to Celtic after agreeing a one-year contract extension until the end of the 2011/12 season.
Defender Wilson's existing deal was due to expire at the end of the current campaign and his new contract includes the option to extend his stay for a further year.
A Celtic statement read: "Celtic Football Club is delighted to announce that Mark Wilson has agreed a new one year contract with the club, with Celtic having the option of a further year.''
In other news, Celtic manager Neil Lennon has been handed a suspended fine by the Scottish Football Association following his latest appearance in front of the general purposes committee.
Lennon is currently in the middle of a four-match ban imposed following his dismissal against Hearts in November and subsequent reaction, which saw his automatic ban doubled for "excessive misconduct'' in a decision finally reached following an appeal earlier this month.
Now the Celtic boss has been handed a suspended financial penalty following the match at Tynecastle.
A Scottish FA statement read: "The general purposes committee today imposed a fine of £5,000 on Celtic manager Neil Lennon, suspended until June 30, 2012, for remarks made following the tie between Heart of Midlothian and Celtic in the Scottish Premier League on November 10, 2010.''
Lennon is currently at the centre of a dispute between the SFA and Celtic after further disciplinary action was taken against the Bhoys boss in the wake of the volatile March 2 Scottish Cup clash with Rangers.
His angry reaction to comments made by Rangers assistant boss Ally McCoist at the end of Celtic's 1-0 Old Firm derby success led to a misconduct charge, automatically triggering a second ban.
On Wednesday the Bhoys decided against appealing the four-match suspension for the clash with McCoist to take into consideration "the wider interests of the club and Scottish football''.
But they also declared that Lennon would be serving the ban concurrently with the suspension received following the Hearts match, meaning he would sit out a total of five games.
The SFA's position is understood to be that both bans will run consecutively, meaning Lennon would sit out a total of eight matches, but SFA chief executive Stewart Regan refused to comment on the situation on Thursday.
Celtic's case is based on the rule that a punishment begins 14 days after the offence but the SFA are seeking legal advice over the issue.
"I'm not able to talk about Neil Lennon or Celtic at the moment,'' Regan said today as the SFA launched their performance strategy. "We're in the middle of a live case and we're not able to get into it. There are legal implications on both sides of this particular case.''
The second match of Lennon's current ban was last night's Scottish Cup clash at Inverness, which Celtic won 2-1.
Meanwhile, the Scottish Premier League have announced Celtic's postponed match with Hibernian will now take place on April 6.
The Parkhead clash was originally scheduled for Wednesday night but was delayed by the postponement of Celtic's Scottish Cup quarter-final against Inverness, which the Bhoys won 2-1. The match will kick-off at 7.45pm.
Celtic's progression in the Scottish Cup means their match at St Johnstone, scheduled for April 16, has been postponed, with a new date yet to be determined.