After starting his professional career with Portland Timbers, he moved to England to join Millwall in 1992, playing four seasons at the London club.
Three years at Leicester City followed before he moved on a free transfer to join Spanish club Rayo Vallecano in 1999.
After two years in Spain he moved back to the Premier League to play for Tottenham, eventually becoming first choice.
A short stint on loan with Southampton followed before he enjoyed two years in Germany with Borussia Monchengladbach.
Keller was not quite done with the English game and returned once again to play briefly for Fulham in the 2007/08 campaign.
His final act domestically was a three-year spell with new MLS side Seattle Sounders before calling time on his playing career in 2011.
Keller was a regular for the United States national side between 1990 and 2007, making 102 appearances and is widely regarded as the best goalkeeper to have played for his country.
He has worked as a TV pundit and commentator for ESPN and spent time coaching the USA Under-20 side.
The early years
Keller was born in Olympia, Washington and played for the University of Portland, earning praise for his displays in goal. He was selected as an All-American in 1990 and named Goalkeeper of the Year in 1991.
He played for the Portland Timbers during the 1989 college off-season, keeping eight clean sheets in 10 matches to earn the Western Soccer Alliance's MVP award.
His star was on the rise and, in 1989, he spent time playing for Portland and the USA Under-20 side that finished fourth at the 1989 FIFA World Youth Championship.
They were beaten 2-0 by Brazil in the third-place play-off but Keller excelled, winning the Silver Ball for the tournament's second best player in Saudi Arabia.
He was selected for the USA full national side in 1990 and it was no surprise when clubs started to take note of his prowess between the posts.
Career at Millwall and Leicester City
Keller signed for Millwall and played at the Den between 1992 and 1996, becoming a favourite of the home fans. He made 176 league appearances for the Lions and was voted the club's Player of the Year in 1992/93.
He made his debut on May 2, 1992 and played his last game on May 5, 1996, amassing 202 appearances in all competitions.
With the club suffering relegation at the end of the 1995/96 season, he secured a £900,000 move to Leicester City in the summer of 1996.
Kasey Keller, Leicester City, 1996
Keller enjoyed 99 league outings for the Foxes while picking up his first and only piece of silverware in the English game.
That came in the 1997 League Cup final against Middlesbrough which Leicester won 1-0 in a replay after the first game had ended 1-1.
Leicester reached the League Cup final again two years' later but went down 1-0 to Tottenham, with Spurs' Allan Nielsen scoring a last-minute goal to lift the trophy for the north Londoners.
With his contract in the East Midlands expiring, Keller decided to try his luck in another country and left Leicester to join Rayo Vallecano in the summer of 1999.
Spell at Rayo Vallecano and move to Tottenham
Keller's move to Spain with Rayo Vallecano lasted for two seasons and he made 51 league appearances for the Madrid-based club before leaving to join Tottenham on a free transfer in August 2001.
Kasey Keller, Rayo Vallecano, 2000
Things began slowly at Spurs and the American found himself on the bench, acting as back-up to Neil Sullivan.
However, after appearing in cup games and taking his chances when they arose, he finally made the goalkeeper's shirt his own.
Despite playing in the 2002 Gold Cup for the USA and missing time at his club, he returned to play seven league games for Spurs, ending the campaign with a 2-1 loss to former club Leicester.
Keller played every minute of Tottenham's 2002/03 and 2003/04 seasons, making 85 Premier League appearances in total for the north London club.
However, the arrival of Paul Robinson from Leeds United signalled the end of his time at Spurs and, relegated from the league side, he moved to Southampton on a one-month loan in November 2004, playing four times for Saints.
He did not play again for Tottenham and it was inevitable that at the end of the 2004/05 campaign he would be on the move once again.
Borussia Monchengladbach and move to MLS
Keller joined Bundesliga club Borussia Monchengladbach during the 2005 January transfer window and was made first-choice goalkeeper by head coach Dick Advocaat.
He played every minute in the league during the second half of the 2004/05 campaign, endearing himself to the fans with a series of outstanding displays which included keeping seven clean sheets.
His skills between the posts enabled Die Fohlen to stay in Germany's top division. He made a total of 78 league appearances for Gladbach and was named captain of the team for the 2006/07 season before moving back to England to join Fulham.
Initially with the Cottagers, Keller was placed on the bench as reserve keeper to Antti Niemi, but injuries to the Finland international saw him promoted to the starting XI.
However, Keller injured his arm ahead of a match in October 2007 and was out of action until late January 2008. He found himself back on the bench after recovering from the injury but did regain his starting berth and played in the final 10 league games of the campaign.
Fulham beat Portsmouth 1-0 on the final day of the season to maintain their Premier League status.
Keller left Fulham to return stateside in the summer of 2008 and made his debut for new MLS side Seattle Sounders in March 2009.
He made 93 appearances for the Washington outfit over three seasons before calling time on his playing career in October 2011.
International career with the United States
Having impressed for the USA youth teams, Keller was called up to the full USA side in 1990 and selected for the 1990 World Cup in Italy.
He did not play a match in the tournament, acting as Tony Meola's back-up as the Americans lost all three group games to crash out of the event.
He failed to dislodge Meola and, with Brad Friedel emerging on the scene, was left out of the 1994 World Cup squad by coach Bora Milutinovic.
For many years, Keller fought a battle with Friedel to wear his national colours but he began to see playing time from 1995 onwards, playing in the Copa America that year.
He played in the 1996 Gold Cup and in qualification for the 1998 World Cup, although Friedel was still very much part of the picture.
Coach Steve Sampson selected him for the 1998 World Cup in France and he played in the first two group games before making way for Friedel in the third.
Kasey Keller, United States, USA, 1997
The USA lost all three games in what was a disappointing campaign for the Stars and Stripes.
In the semi-finals of the 1998 Gold Cup against Brazil, Keller produced one of his best displays, making 10 saves as his side beat the South Americans 1-0.
Friedel got the nod for the 2002 World Cup with Keller on the bench but he returned to play all three games at the 2006 World Cup in Germany.
Despite earning a draw with Italy, the Americans were eliminated at the group stage.
He lifted the Gold Cup in 2005, with the USA beating Panama on penalties in the final after the match ended goalless in 120 minutes.
He made 102 appearances for the USA, with his final outing against Paraguay in March 2007, and is widely recognised as his nation's greatest goalkeeper.
He was inducted into America's National Soccer Hall of Fame in October 2015.
Kasey Keller in management
Keller dipped his toe in the coaching world by helping out the USA U20s as they prepared for the 2013 World Cup.
Head coach Tab Ramos invited him to join up for a week's training camp in California to lend his vast experience of the international game to the youngsters involved.
At the time he said: "They're a team and I'm just coming in to help out and do what I can. It's been a real positive experience. I've spent 25 years of my life as a National Team player, either through the youth or through the full team and to be able to give some of that experience back is great."
He did not want to take on the role full-time as it would interfere with his duties working as a broadcast analyst with the Sounders FC. He did not return to coaching after the spell ended.
Personal Life
Keller lives in Seattle with wife Kristin. They have twins, Cameron and Chloe, who were born in 1997.
He has revealed that he could have continued playing in Europe towards the end of his career and had several offers but chose to return to the USA to play for Seattle and give his children some stability with their schooling.
Having played in Germany and Spain as well as England, he is fluent in Spanish and German. During his time living in Germany, he and his family resided in a 1,000-year-old castle.
He has worked as a studio analyst for ESPN for a number of years, providing insight into MLS games as well as those involving the national side.
He is a well-respected broadcaster, having earnt the right to state his opinion by making more than 100 appearances for the USA in a stellar playing career.