MIAMI, FL, USA - Battling from behind in both sets, Venus Williams booked her spot in the third round of the Miami Open on Friday with a titantic two-set victory over Russian Natalia Vikhlyantseva, 7-5, 6-4.

The No.8 seed trailed 5-2 in the opening set before winning five straight games, and also trailed 3-0 in the second set before winning six of the last seven games to prevail in two hours and seven minutes.

"She hit every unexpected shot and what can you do except clap on those shots? Thankfully, I was able to find a way to win this match," Williams said after the match.

"At the end, you try to win the last point and walk towards the net as the winner of the last point. I think that's what I worked towards, and got there."

Blasting powerful groundstrokes from the baseline, the 21-year-old World No.88 routinely put Williams on the back foot for much of the first set, as she broke serve twice en route to building a 5-2 lead.

Vikhlyantseva's emphatic tennis continued in the eighth game, as she carved out two set points on a 114 mph ace out wide, but she was unable to convert either chance to take a one-set lead.

A double fault erased the first set point, and Williams walloped a forehand return winner down the line on a second serve to save the second, before another backhand winner gave her break point. 

She duly converted as Vikhlyantseva put a forehand wide to put the set back on serve, and the three-time champion swung momentum in her favor once more by winning a titantic 11th game.

"She was playing well," Williams added. "It was really only one break, so getting that break back was huge."

In an 18-minute game on the Russian's serve which featured 11 deuces, she was unable to convert on eight game points to reestablish her lead, and Williams pocketed her third straight game as Vikhlyantseva's forehand sailed long of the baseline on a fourth break point. 

Missed chances were the story of the end of the set for the World No.88, as she was unable to convert on two further break points as the American served out the set. 

However, Vikhlyantseva quickly shook off any disappointment to begin the second set, as a pair of emphatic holds sandwiched a third break to give her a 3-0 lead. 

However, Williams proved clutch when facing a deficit once again, as she saved a break point which would've seen her trail 0-4, and got the set back on serve in short order.

Though Vikhlyantseva would break again to restore a lead at 4-2, that proved to be the last game she'd win in the match as the No.8 seed won the last four to book a third round meeting with No.29 seed Kiki Bertens.