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 |  |  | | Nathaniel Kosarich |  | | Residence: | Tampa, FL |
| Birthplace: | Unknown | | Age: | Unknown | | Height: | Unknown | | Plays: | Unknown | | Coaching: | Unknown |  | | Complete Bio | |
New Year's Kickoff, January 8, 2011
 Englewood TC Super Series, February 12, 2011
 Longwood Super Series, February 19, 2011
 Countryside Jr. Local Chmps., February 26, 2011
  |  |  Rnd |  Result |  Opponent |  Rank |  Score | | 16 | Win | Caleb Littlestone | | 6-0; 6-1 | | Q | Win | Facundo Arias | 2363 | 6-2; 6-0 | | S | Win | Rhys Richardson | | 2-6; 6-3; 10-7 | | F | Loss | Parker Hayslett | | 6-2; 6-4 |
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Saddlebrook March Local, March 5, 2011
 Scott Linder Jr. Super Series, March 12, 2011
 Bardmoor Super Series, March 19, 2011
  |  |  Rnd |  Result |  Opponent |  Rank |  Score | | Q | Win | Martynas Lukosiunas | | 6-4; 7-6(3)) | | S | Loss | Bailey Showers | 90 | 6-1; 6-1 |
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Bath & Racquet Super Series, April 1, 2011
 Winter Haven Spring Super Series, April 9, 2011
  |  |  Rnd |  Result |  Opponent |  Rank |  Score | | S | Win | Stephen Jordan | | 6-2; 6-2 | | F | Loss | Holleman Hughes | 464 | 6-0; 2-0Ret (inj)RJ |
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Hunter's Green Local Chmps., April 16, 2011
 Saddlebrook Jr. Super Series, May 7, 2011
 BSAC Tennis Local Summer Kick-off, May 14, 2011
 SPTC Jr. Open Local, June 4, 2011
 USTA Florida Closed Sectional BG18-14, June 11, 2011
 Clearwater Hot Shot Super Series, June 18, 2011
  |  |  Rnd |  Result |  Opponent |  Rank |  Score | | 16 | Win | Joshua Bode | 654 | 6-0; 6-0 | | Q | Win | Foresight Okungbowa | | 6-2; 6-0Ret (inj)RJ | | S | Loss | Parker Hayslett | | 6-7; 6-4; 10-7 |
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Temple Terrace Local Summer Bash, June 25, 2011
 Seminole Lake TC July Spectacular, July 2, 2011
 USTA Regional Tourn. (Ponte Verde), July 9, 2011
 North Florida Designated BG18-12, July 23, 2011
 Bollettieri-IMG Academies Jr. Chmps., July 30, 2011
 SPTC Jr. Super Series, August 20, 2011
 USTA Regional Tourn. (Delray Beach), September 3, 2011
 Ledger Jr. Super Series, September 17, 2011
 Super Series Seminole Bash, September 24, 2011
 Seminole Co. Fall Des. BG14,G16, October 8, 2011
 Hunter's Green Local Clay Challenge, October 29, 2011
  |  |  Rnd |  Result |  Opponent |  Rank |  Score | | 16 | Win | Alan Williams | | 6-2; 6-1 | | Q | Win | Jean-Brice Duhamel | | 6-0; 6-1 | | S | Loss | CAN Erem | | 6-3; 7-6(7-5) |
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Bill Clark Fall Designated B14, November 5, 2011
 Winter at Winter Haven Super Series, December 17, 2011
  |  |  Rnd |  Result |  Opponent |  Rank |  Score | | S | Loss | Brian Berdusco | 525 | 6-2; 4-0Ret (inj)RJ |
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Seminole Lake TC New Year's Super Series, December 28, 2011
 + Strong win over an ineligible player. * The ranking calculation does not count this match.
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