Venus Williams displayed the mental strength that has made her a seven-time Grand Slam singles champion on Thursday, holding off a spirited challenge by Slovenian Dalila Jakupovic at the WTA Miami Open.

The American, 38, a quarter-finalist at Indian Wells last week, turned back Jakupovic 7-5, 6-3 to reach the second round after a rough start. Venus credits her mother, Oracene Price, with instilling the character and desire to match the tennis skills developed by their father and coach Richard Williams.