(CNN) -- Bolton midfielder Fabrice Muamba has been pictured for the first time since collapsing on the pitch with a cardiac arrrest during his side's FA Cup quarterfinal match against Tottenham Hotspur at White Hart Lane on March 17.
Muamba is shown smiling and sitting up on his bed at the London Chest Hospital where he is recovering from his ordeal.
The photograph was posted Friday on the Twitter account of his girlfriend Shauna.
"Fab wanted me to post this pic for you all and to also say thank you for such overwhelming support," read the message with the picture.
The 23-year-old is wearing a T-shirt and hooded top, but is in a room full of medical equipment.
Muamba collapsed during the first half of the game at Tottenham, being stretchered off while horrified players and fans watched on. It was also being shown on television.
The match was abandoned, with Tottenham winning the replayed tie 3-1 earlier this week.
It was later revealed Muamba's heart had stopped for 78 minutes while desperate, but in the end successful, attempts were made to resuscitate him.
Meanwhile, English Premier League side Aston Villa said Friday that their captain, Stiliyan Petrov, has been diagnosed with acute leukaemia.
The 32-year-old Bulgarian international midfielder had undergone medical tests after going down with a fever following Villa's 3-0 defeat to Arsenal last Saturday.
"We expect to learn more about Stiliyan's situation in due course and we have moved quickly to support him and his family," the statement on the club's official website said.
"During this time we ask that Stiliyan's privacy is placed ahead of all inquiries and trust that we will share information as we receive it.
"Stiliyan is cherished by many and he will get from Villa every ounce of love and support that we have to help bring this to a positive conclusion."
Petrov, who has been capped 105 times by Bulgaria, joined Aston Villa in 2006 after spending seven years with Scottish giants Celtic where he was a big crowd favorite and helped them to four championship titles.
"We are all absolutely devastated to hear this news. As a member of the Celtic family, it is important for Stiliyan to know that he has our unequivocal support in battling against this disease," manager Neil Lennon said in a statement on the club's official website.