[3] Between 2000 and 2012, Sørensen was the starting goalkeeper for the Denmark national football team, the successor to the legendary Peter Schmeichel, and he played 101 matches for his country, making him their eighth-most capped player of all time.

He played in training matches against FC St. Pauli and Werder Bremen in February 1993, and signed a trainee contract with the club.

Odense then loaned him out again, this time to FC Svendborg in the second-tier Danish 1st Division league,[10] where he played the full 1997–98 season.

Hardly anyone outside of Denmark had even heard of the tall and athletic keeper,[11] when English manager Peter Reid bought the 22-year-old from Odense for about £510,000 in July 1998.

This move helped Sunderland to promotion for the top flight English Premiership, when Sørensen and his team grabbed the League Championship title in 1999.

He gained legendary status with Sunderland fans in 2001, when he saved a penalty kick from Alan Shearer in the dying moments of a November 2000 game, to preserve a valuable win over archrivals and neighbouring club Newcastle United.

Sørensen's ability as a shot stopper allowed him to retain his place as Villa's number one under both managers David O'Leary and Martin O'Neill, ahead of the likes of Stefan Postma and Stuart Taylor.

[19] He failed to make a single appearance for the club in his final season as by then he had slipped down to third place in the pecking order behind both Scott Carson and Stuart Taylor.

On 28 July 2008, Sørensen started a trial with newly promoted Premier League team Stoke City, and two days later, he signed a three-year contract with the club.

He saved penalties during games against Portsmouth,[24] Arsenal[25] and Wigan Athletic,[26] and played an important part in Stoke's good run in the league, which brought them to 10th place in December.

[28] Sørensen got extra competition for the spot as Stoke's first-choice goalkeeper, following the signing of Asmir Begović from Portsmouth in February 2010.

Once Begović returned from his injury Butland was loaned out to Leeds United, leaving Sørensen to resume his place as back-up for the remainder of the 2013–14 season and was offered a one-year contract extension,[42] which he signed in May 2014.

[45] Sørensen decided to mark his departure from Stoke by cycling 4,000 miles across the United States to raise money for charity.

Following his initial impressive form for Vejle, he was called up for an unofficial national team game in April 1996, and replaced Lars Høgh at half-time.

After his move to Sunderland, Sørensen made his debut for the senior Danish national team in November 1999 in a match against Israel, coming on to replace an injured Peter Schmeichel.

Sørensen's elbow injury put his chance of appearing in his second World Cup in doubt,[30] but Denmark coach Morten Olsen included him in the final squad, and on regaining full fitness Sørensen was named the starting goalkeeper for his second World Cup campaign, and played full-time in Denmark's three games at the tournament.

[53][54] On 26 May, in a friendly against Brazil at Hamburg's Imtech Arena, Sørensen had to be substituted for an injury in the 24th minute[55] which led to his withdrawal from Denmark's squad for UEFA Euro 2012.

[59] In 2006, Sørensen became an investor in Golf Punk magazine, alongside former Sunderland teammates Phil Babb, Michael Gray, Jason McAteer, and Stephen Wright, saving the publication from closure.

Sørensen also actively appears as a guest on the network's 'GegenPod' podcast, providing punditry input to Australia's A-League, Socceroos national team fixtures and European leagues.

Additionally, Sørensen was present in covering UEFA Euro 2020 and Copa America 2021 fixtures, as well as the 2023 FIFA Women's World Cup, appearing as a panellist during pre and post game intervals.