In winning his sixth career title, the 35-year-old Santoro became the oldest player to win the tourney on the International Hall of Fame's grass courts. Andre Agassi won three events in 2005 when he was 35-years old.
Amritraj, the son for three-time Newport winner Vijay Amritraj and a wild-card entry, was the lowest ranked player to reach a Newport final. India's Davis Cup member entered the week 305th in the world.
Santoro, who earlier in the week said he was likely to be cutting back his tour play next year, won his 451st match, fourth among active players behind Roger Federer, Carlos Moya and Lleyton Hewitt.
"When you start a career at 16 years old, never, ever can you imagine you'll win a tournament 20 years later. I played my first French Open in 1989,'' Santoro said. "I have the same passion for the game as five, 10, 15 years ago, maybe more.''
It was just the second No. 1 or No. 2 seed to win the finale in the tourney's 32-year history; Johan Kriek did it in 1981.
Vijay Amritraj, who won 13 titles in 26 career finals, watched his son from behind one of the baselines.
"We talked after the match. He told me my strategy was right, but I just needed to be a little more aggressive,'' Prakash said.
After getting broken in the first game of the match, Santoro broke right back en route to winning four straight games. Amritraj's consecutive unforced errors closed out the second game.
"I think I was broken three times this week, and every time I broke right back,'' Santoro said.
Amritraj made three unforced errors in the final game of the opening set before Santoro closed it out with forehand off a net ball.
Santoro had the only break in the second set, taking a 6-5 lead, before hitting a backhand passing shot at 40-love to win the match. He raised both hands in triumph.
"I'm just very happy on the court, to have the trophy in my hands,'' he said, smiling.
Santoro collected $64,000 for the title and Amritraj earned $32,000.
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