The Association of British Bookmakers acted after a number of bets were placed on there being a red card during Motherwell's 2-1 defeat.

Jennings, after being booked by referee Stevie O'Reilly for a foul on Kevin Kyle, was shown a straight red card seven minutes from the end after putting his hand on the official's shoulder and speaking to him about a rejected penalty claim.

Jennings is understood to have asked the referee when he was going to stop 'cheating' Motherwell.

It is understood that several bets were put on a red card being dished out in the Clydesdale Bank Premier League clash at Fir Park, including one from a new account opened in Liverpool, where a £500 bet was placed at odds of 10/1.

Former Tranmere midfielder Jennings said he was in "shock" over the probe.

He told the Scottish Sun: "I want to make it clear I had no involvement whatsoever in any betting scam. I want to clear my name as quickly as possible."

Motherwell chairman John Boyle stood by Jennings .

He said in the Daily Record: "I'd be amazed if Steve got himself involved in anything like that.

"I was in the dressing room after the match and the player was totally distraught.

"If that wasn't genuine emotion from him he is a better actor than Laurence Olivier. I think this whole thing is mischief-making.

"I'd be astonished by any allegations or implications."

One bookmaker told Press Association Sport: ``It is all to do with a bookmaker's instinct when it comes to irregular betting.

``It can be a small number of large bets or a large number of small bets.

``A regular punter making an irregular bet or a new account being opened and a large amount of money put on an unusual bet can also ring alarm bells.

``But as I say, instinct plays a huge part.''

The SFA is joining forces with the Scottish Premier League in a bid to get to the bottom of the incident.

The SFA issued a statement which read: ``Following information received from the Association of British Bookmakers (ABB), we are aware of alleged betting irregularities surrounding a sending-off incident in the Motherwell v Heart of Midlothian match on Tuesday.

``At this stage, we are not in possession of the facts regarding the allegations and are waiting for further information from the Scottish Premier League in due course.

``Once we are in possession of all of the facts we will be in a better position to provide more detailed comment on the matter.

``In the meantime, we will be working with our colleagues at the Scottish Premier League to establish the details surrounding this incident.''

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