Norfolk is the first player to win a quad title at the US Open

Norfolk had already beaten Wagner in the second of three round-robin matches on Friday, reaching the final unbeaten.

Norfolk's win is all the more remarkable as he has spent four months out with a shoulder injury.

The Briton will now continue his quest to reclaim the world number one ranking in next week's Atlanta Masters Series.

Interview: Peter Norfolk

Norfolk started strongly and went 5-1 ahead in the opening set but he then found himself unable to clinch the set as Wagner gradually chipped away at the Briton's lead.

Wagner levelled the scores at 5-5 and then broke again to move 6-5 ahead but Norfolk held his nerve in a tense 12th game, saving four set points before forcing a tie-break on his third break point.

The Athens Paralympic champion then clinched a mini-break in the tie-break to go 6-5 up and gain his first set point of the match before holding his serve to see out the set.

Norfolk secured the first break of the second set in the third game and then secured another break after the seventh game went to deuce to lead 5-2 and he served out on the first of his three match points to clinch the title.

The men's and women's singles titles went to top seeds and world number ones Shingo Kunieda of Japan and Holland's Esther Vergeer.