| Norman ITF | Round | Result | H | A | 
		
			| 16.11. |  | Miyazaki Y. - Guillermo L. | QF | 7-5, 5-7, 6-1 | 2.53 | 1.46 | 
		
			| 15.11. |  | Guillermo L. - Podoroska N. | R16 | 6-1, 3-6, 7-5 | 5.00 | 1.13 | 
		
			| 13.11. |  | Guillermo L. - Chang H. | 1R | 6-4, 6-4 | 2.83 | 1.42 | 
		
			| Stockton ITF | Round | Result | H | A | 
		
			| 01.10. |  | Gumulya B. - Guillermo L. | Q-1R | 7-5, 7-5 | 2.45 | 1.49 | 
		
			| Templeton ITF | Round | Result | H | A | 
		
			| 23.09. |  | Elie J. - Guillermo L. | Q-1R | 7-62, 6-4 | 1.45 | 2.56 | 
		
			| Fort Worth ITF | Round | Result | H | A | 
		
			| 02.08. |  | Mateas M. - Guillermo L. | R16 | 6-2, 6-2 | 1.43 | 2.63 | 
		
			| 31.07. |  | Guillermo L. - Black H. | 1R | 7-65, 6-0 | 1.50 | 2.42 | 
		
			| Ashland ITF | Round | Result | H | A | 
		
			| 23.07. |  | Manasse M. - Guillermo L. | Q-R16 | 6-4, 6-0 | 1.68 | 2.06 | 
		
			| 22.07. |  | Guillermo L. - Kobelt M. | Q-1R | 4-6, 6-2, 6-0 | 1.21 | 3.91 | 
		
			| Berkeley ITF | Round | Result | H | A | 
		
			| 18.07. |  | Manasse M. - Guillermo L. | 1R | 6-4, 6-2 | 1.56 | 2.28 | 
		
			| 17.07. |  | Guillermo L. - Santamaria S. | Q-QF | 2-6, 6-1, 7-68 | 2.33 | 1.52 | 
		
			| 16.07. |  | Guillermo L. - Mossmer N. | Q-R16 | 5-7, 6-3, 6-1 | 1.18 | 4.13 | 
		
			| 16.07. |  | Guillermo L. - Gabueva A. | Q-1R | 3-6, 6-1, 6-2 | 1.66 | 2.08 | 
		
			| Winnipeg ITF | Round | Result | H | A | 
		
			| 12.07. |  | Sema E. - Guillermo L. | R16 | 6-4, 6-3 | 1.40 | 2.70 | 
		
			| 11.07. |  | Guillermo L. - Andreescu B. | 1R | 3-6, 6-4, 4-2 | 11.40 | 1.01 | 
		
			| 08.07. |  | Guillermo L. - Bui J. | Q-R16 | 6-3, 6-1 | 1.20 | 4.17 | 
		
			| Hua Hin 12 ITF | Round | Result | H | A | 
		
			| 03.06. |  | Montez P. - Guillermo L. | Q-2R | 6-4, 6-2 |  |  | 
		
			| Hua Hin 11 ITF | Round | Result | H | A | 
		
			| 29.05. |  | Robinson M. - Guillermo L. | 1R | 6-3, 7-65 | 2.27 | 1.55 | 
		
			| 28.05. |  | Guillermo L. - William T. | Q-R16 | 6-4, 6-4 | 1.12 | 5.36 | 
		
			| 27.05. |  | Guillermo L. - Silakul C. | Q-2R | 6-1, 6-4 |  |  | 
		
			| Hua Hin 9 ITF | Round | Result | H | A | 
		
			| 11.05. |  | Thamchaiwat B. - Guillermo L. | SF | 7-64, 6-3 | 1.34 | 2.98 | 
		
			| 10.05. |  | Guillermo L. - Momkoonthod T. | QF | 6-4, 6-3 | 1.16 | 4.43 | 
		
			| 09.05. |  | Guillermo L. - Sheng Y. | R16 | 6-3, 6-2 | 1.14 | 4.80 | 
		
			| 07.05. |  | Guillermo L. - Walters A. | 1R | 6-1, 6-1 | 1.05 | 7.69 | 
		
			| Hua Hin 8 ITF | Round | Result | H | A | 
		
			| 02.05. |  | Ma S. - Guillermo L. | R16 | 7-62, 6-2 | 3.86 | 1.21 | 
		
			| 01.05. |  | Guillermo L. - Zhu A. | 1R | 6-3, 6-3 | 1.22 | 3.81 | 
		
			| Rancho Santa Fe ITF | Round | Result | H | A | 
		
			| 22.02. |  | Li A. - Guillermo L. | R16 | 7-62, 6-3 | 1.29 | 3.27 | 
		
			| 22.02. |  | Guillermo L. - Day K. | 1R | 6-3, 7-65 | 6.07 | 1.10 | 
		
			| 20.02. |  | Guillermo L. - Larcher de Brito M. | Q-R16 | 6-2, 6-4 | 2.92 | 1.36 | 
		
			| 19.02. |  | Guillermo L. - Werner C. | Q-2R | 6-3, 6-2 |  |  | 
		
			| 18.02. |  | Guillermo L. - Haynes J. | Q-1R | 6-3, 6-1 |  |  | 
		
			| Surprise ITF | Round | Result | H | A | 
		
			| 11.02. |  | Partaud M. - Guillermo L. | Q-1R | 6-4, 7-5 |  |  |