The 37-year-old has won 102 caps for his country but is contemplating calling it a day after his release from German side Borussia Monchengladbach.

He said: "If in the upcoming four to six weeks I don't find a team I would like to go on playing for for at least one or two seasons at the top level, retirement is a possibility."

Keller has played in four World Cups and is the only survivor of the American side which reached the last four at the 1995 Copa America in Uruguay.

His experience makes him an attractive proposition for many clubs with Keller revealing he has had offers from "seven or eight interested parties".

However, he will discuss any possible move with his family before coming to a decision.

"At the age of 37, I've played in three of the most important leagues," the former Tottenham Hotspur and Rayo Vallecano custodian said.

"My children are nine years old and have been in three different countries and gone to three different schools."

The USA lost 3-1 to Paraguay on Monday and are unlikely to progress to the next phase of the Copa America in Venezuela.