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 |  |  | | William Karpinski |  | | Residence: | Potomac, MD |
| Birthplace: | Unknown | | Age: | Unknown | | Height: | Unknown | | Plays: | Unknown | | Coaching: | Unknown |  | | Complete Bio | |
David Lemair Tennis Jr. Open L5, April 28, 2012
 USTA MAS B12 Challenger #3, May 5, 2012
 RPM Sports Jr. Open L4, June 13, 2012
  |  |  Rnd |  Result |  Opponent |  Rank |  Score | | 16 | Win | Devan Geib | 414 | 6-4; 6-0 | | Q | Win | Neehar Chadeva | 850 | 6-1; 6-0 | | S | Win | Oscar Levine | | 2-6; 6-4; 1-0 | | F | Loss | Carter Davis | | 1-6; 6-2; 1-0 |
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USTA MAS BG12 Chmp. #3, June 20, 2012
 American University Jr. Open #1, June 30, 2012
  |  |  Rnd |  Result |  Opponent |  Rank |  Score | | 32 | Win | Pascal Lee | 291 | 6-1; 2-6; 1-0(3) | | 16 | Loss | Conor Smyth | | 6-2; 6-0 |
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USTA MAS B14 Challenger #4, July 7, 2012
  |  |  Rnd |  Result |  Opponent |  Rank |  Score | | 64 | Loss | Austin Yannone | | 6-1; 6-0 |
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USTA Zonal BG12 - Knoxville, July 25, 2012
 Tennis Life Bethesda Jr. Open L4, August 11, 2012
 USTA MAS B12 Challenger #5, August 18, 2012
 USTA MAS B12 Challenger #6, September 15, 2012
 David Lemair Tennis Jr. Open, September 22, 2012
 USTA MAS B12 Championship #4, October 13, 2012
 USTA MAS B12 Challenger #8, December 8, 2012
 USTA MAS B12 Chmp. #1 L1, January 12, 2013
 USTA MAS B12 Challenger #1, February 9, 2013
 USTA MAS B12 Chmp. #2, March 9, 2013
 + Strong win over an ineligible player. * The ranking calculation does not count this match.
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