GLASGOW, Scotland -- Scottish footballer Phil O'Donnell died after collapsing during his team Motherwell's match against Dundee United on Saturday.
Phil O'Donnell pictured during his spell with English club Sheffield Wednesday.
The 35-year-old club captain was taken off the pitch at Fir Park on a stretcher in the closing stages of the Scottish Premier League match, which his side won 5-3.
Motherwell's next two matches, against Hibernian on Wednesday, and Celtic at the weekend, have been postponed.
"The players, the supporters, every one inside the executive are devastated and absolutely dumbfounded by the event of Phil's death," manager Mark McGhee said on Sunday.
"We had a meeting this morning with the players and obviously they have taken it very, very badly and we are going to have to help them through that."
O'Donnell, who started his career at Motherwell before stints with Celtic and Sheffield Wednesday, was about to be substituted at Fir Park against Dundee United but collapsed before he could leave the field.
He was set to be replaced by substitute Marc Fitzpatrick, but fell to the pitch as the change was taking place.
After been treated for about five minutes on the field, O'Donnell was carried off on a stretcher to a waiting ambulance.
Medical staff from both clubs said that they thought he suffered a seizure, and efforts were made to revive him en route to hospital.
However, he did not regain consciousness and was pronounced dead at 1718 GMT (1218 EST).
O'Donnell's nephew, David Clarkson, who scored twice in the match, was also taken off after being alarmed by the incident.
Club chairman Bill Dickie said: "Unfortunately I can confirm very, very sad news that Phil O'Donnell has lost his life. We don't know what it was but there will be a post-mortem.
"This is a tragic happening and that's all I can say."
Motherwell owner John Boyle said: "Everyone here is shocked to the core, and we are sure that everyone involved in Scottish football will feel the same.
"Phil was not only an inspirational player for Motherwell and club captain, but was an inspirational person. All of us at Motherwell are thinking of his wife Eileen and their four children."
McGhee added: "I don't want to say anything more than how devastated everyone at the club is for his wife and his young children. Obviously from the club's point of view, we'll gather round to give his family as much support as they need."
O'Donnell, who won one Scotland international cap, began his career with Motherwell and rejoined the club in 2004 following spells with Celtic -- who he joined in a $3.5 million transfer in 1994 -- and English side Sheffield Wednesday.
Scottish Football Association chief executive Gordon Smith said: "This is absolutely devastating news. Phil was not just a wonderful footballer, he was a great human being. My thoughts are with his family at this tragic time."
Celtic chief executive Peter Lawwell added: "When the news came through, everyone at the club was obviously shocked.
"Our thoughts are with his family to whom we offer extreme condolences for a tragic loss of a young life. Everyone at Celtic Park will mourn him."
O'Donnell is the second Motherwell player to pass away unexpectedly in the past 20 years.
Club legend winger Davie Cooper died at the age of 39 in 1995 after suffering a brain haemorrhage when filming a training video.
Cooper had been a Motherwell team-mate of O'Donnell, who made his debut as a 17-year-old.
He went on to score, as a 19-year-old, in the 4-3 victory over Dundee United in the 1991 Scottish Cup final, and won his sole Scotland cap in 1993 as a substitute in the World Cup qualifier against Switzerland.
Former Scotland manager Craig Brown gave O'Donnell his only international outing, and had coached him in the Under-21 side.
"But for injury, I'm sure he would have had many, many more caps," Brown said. "It's very, very sad news, I just can't get over it. You would not get a more ideal role model for a young footballer than Phil O'Donnell.
"I think in his first spell at Motherwell he was probably the best box-to-box midfield player -- maybe not just in Scotland but in the UK."
Injuries affected O'Donnell's spells with Celtic and Sheffield Wednesday and he returned to Motherwell after being released by Wednesday in early 2004.
He played in the 2005 Scottish League Cup final, and was appointed captain in 2006 after former skipper Scott Leitch left the club.
Football has suffered several other deaths in recent years.
Cameroon midfielder Marc-Vivien Foe collapsed and died at the 2003 Confederations Cup in France, prompting world ruling body FIFA to demand stricter physical testing on players.
Sevilla midfielder Antonio Puerta died in August after he collapsed on the field during a Spanish league game due to heart problems.
Striker Chaswe Nsofwa died of heart failure while training in Israel, and 16-year-old English player Anton Reid died after collapsing while training with his club Walsall. E-mail to a friend
All About Scotland
Scottish football player Phil O'Donnell has died today after collapsing during a game in which his team Motherwell F.C., of which he was captain, were playing Dundee United in a Scottish Premier League match.

O'Donnell collapsed as his substitution for Marc Fitzpatrick was being arranged. He received treatment for around five minutes before being stretchered off and transferred to a waiting ambulance. David Clarkson, O'Donnell's nephew, was also playing at the time and had scored twice but was taken off due to being visibly distressed by O'Donnel's collapse.

Medics from both teams believed he had suffered a seizure. Attempts were made in the ambulance to revive him, but these failed and he was pronounced dead at 17:18 GMT, having been taken to Wishaw General Hospital.

Born on March 25, 1972 O'Donnell made his debut for Motherwell in 1990, and scored the following year in the final of the Scottish Cup, which Motherwell defeated Dundee United 4-3 in. In 1993 he earned his only international cap for Scotland as a substitute in a World Cup qualification match against Switzerland.

The following year he was bought by Celtic for £1.75 million ($3.5 million). He stayed with them for five years, after which he was transferred to Sheffield Wednesday. A high number of injuries caused Sheffield Wednesday to release him after four years, and the next year, 2004, then Motherwell manager Terry Butcher awarded him an 18-month contract. In 2006 he was appointed captain, and in April the following year, upon the expiration of his original contract, signed a new one as a player-coach.

Motherwell chairman Bill Dickie said "Unfortunately I can confirm very, very sad news that Phil O'Donnell has lost his life. We don't know what it was, but there will be a post-mortem. This is a tragic happening and that's all I can say."

Motherwell owner John Boyle told the press "Everyone at Motherwell is shocked to the core, and we are sure that everyone involved in Scottish football will feel the same. Phil was not only an inspirational player for Motherwell and club captain, but was an inspirational person. All of us at Motherwell are thinking of his wife Eileen and their four children."

Mark McGhee, manager of the team, said "I don't want to say anything more than how devastated everyone at the club is for his wife and his young children. That's what we are all feeling tonight, nothing else matters. Obviously from the club's point of view, we'll gather round to give his family as much support as they need." 

In a press conference given at the hospital, Motherwell chief executive Ian Stillie said "The management, directors, players and fans are all stunned and having great difficulty in comprehending what has happened over the last few hours. At this stage we do not have all the facts surrounding the tragic death of Phil O'Donnell. We have been in contact with Phil's wife Eileen and his family and they have given us their blessing to speak to the media tonight. Phil collapsed during the second half of the game today. He was standing alone at the time. He was immediately attended to by Motherwell's club doctor and assisted by Dundee United's club doctor. He was transferred almost immediately to an awaiting ambulance and taken to Wishaw General. It is believed Phil suffered some form of seizure and was pronounced dead at 1718." 

Gordon Smith, Scottish Football Association chief executive, told reporters "This is absolutely devastating news. Phil was not just a wonderful footballer, he was a great human being. My thoughts are with his family at this tragic time." Meanwhile, Celtic chief executive Peter Lawwell said "When the news came through, everyone at the club was obviously shocked. Our thoughts are with his family to whom we offer extreme condolences for a tragic loss of a young life. Everyone at Celtic Park will mourn him."