Howard made 15 saves, the most by any keeper in a World Cup match since 1966 according to statistics, before two goals in extra time saw Belgium win 2-1 to secure a quarter-final place against Argentina.
Klinsmann said: "What Tim played tonight was just phenomenal, outstanding - he kept us in that game for a long time. We are proud to have him with us.
"It was an absolutely amazing match tonight and you can give him the biggest compliment in the world."
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