LONDON -- Bolton midfielder Fabrice Muamba remained in critical condition in intensive care on Monday, two days after suffering a cardiac arrest during an FA Cup match at Tottenham.
The 23-year-old Muamba's heart only started beating on its own again when he arrived at a London hospital's heart attack unit on Saturday night.
"Fabrice Muamba's heart condition is stable, but he remains critically ill in intensive care," the London Chest Hospital and Bolton said Monday in a joint statement.
The player's fiancee has been issuing pleas on Twitter for the health of Muamba, who proposed on Valentine's Day. The couple has a 3-year-old son, Joshua.
Bolton's next match, at Aston Villa on Tuesday in the Premier League, has been postponed. The team is scheduled to play Blackburn on Saturday, and then could face Tottenham again next week in the FA Cup at White Hart Lane to replay the quarterfinal match that was abandoned on Saturday following Muamba's collapse.
"I know the decision will have to be made, but the immediate thoughts are with Fabrice," Bolton captain Kevin Davies said about the possibility of Bolton pulling out of the FA Cup. "I'm sure the club will take a stance on it in the next couple of days."
Davies, who visited Muamba in the hospital over the weekend, said practice would be optional for Bolton players on Monday.
Muamba collapsed near the midfield line in the 41st minute of the FA Cup quarterfinal at Tottenham's White Hart Lane, and paramedics immediately began trying to revive him. Paramedics and an ambulance are now required at matches, following a serious head injury to Chelsea goalkeeper Petr Cech in 2006.
At Tottenham, players were due to undergo tests for potential heart defects.
Sports cardiologist Sanjay Sharma said he was already set to test "one or two players" at Tottenham, but added that now "the players have all demanded cardiac screening."
Uncertainty lingers about what caused the cardiac arrest in Muamba, who has played 33 times for England's under-21 team and was described by former Birmingham manager Steve Bruce as "one of the fittest players I have managed."
The Professional Footballers' Association said there are annual heart screenings for players.
"While we have been able to pick up quite a number (of heart defects) and then been able to put them right, it is not always possible," PFA chief executive Gordon Taylor told The Associated Press. "This sometimes happens to young men and women who would be the last people you would think about having such a defect, and then suddenly it is found out."
Dr. Graham Stuart, a Football Association-accredited cardiologist, said detecting heart defects can be problematic.
"Usually in these cases the reason for this happening is something to do with a heart muscle problem or there is a weakness in the heart muscle," Stuart said. "It could also be a primary arrhythmia disorder -- that is where there is an irregularity in the heart of the ionic channels."
Clive Clarke collapsed because of a cardiac arrest at halftime of a 2007 match while playing for Leicester at Nottingham Forest. He fully recovered, although he never played again.
"They know it was a cardiac arrest, but don't know exactly what brought it on," Clarke told the BBC. "I have now got an internal defibrillator that was fitted while I was at hospital, which hopefully prevents my heart stopping again."
Bolton experienced a similar medical trauma in 2004 when retired Senegal striker Khalilou Fadiga collapsed on the field before a League Cup game, also against Tottenham. He returned to training 11 days after undergoing surgery to treat a heart problem that required an automatic defibrillator to be implanted, and later returned to action.
On Sunday, fans left flowers, Muamba shirts and scarves at Bolton's Reebok stadium, while there were public displays of support in grounds across Europe.
Former Bolton defender Gary Cahill celebrated scoring his first Chelsea goal in an FA Cup match against Leicester by unveiling a "Pray 4 Muamba" T-shirt. In the Spanish capital, Real Madrid players donned "Get well soon Muamba" tops before kickoff against Malaga.
FIFA president Sepp Blatter said on Twitter: "Shocked to hear about Fabrice Muamba. My thoughts are with him and his family, his club & loved ones at this difficult time."
Meanwhile, a man has been arrested after allegedly making racist remarks on Twitter relating to Muamba.
Police say a 21-year-old man from south Wales was held Sunday on suspicion of breaching the Public Order Act, whose provisions include making any acts of racist abuse illegal.
South Wales Police said the man, who allegedly wrote racially offensive comments, was being held in custody in Swansea Central.
Former soccer player turned TV pundit Stan Collymore had urged followers Saturday night to report anyone tweeting racist comments about Muamba to police.
Information from The Associated Press was used in this report.