Britain's Melanie South ousted Italian 11th seed Francesca Schiavone 3-6 6-3 6-4 in the first round at Wimbledon.
South rallied after losing the first set
She was joined in the second round by Sarah Borwell, who beat Pole Marta Domachowska 6-3 6-7 (5-7) 6-4.
Surrey's South looked like making an early exit as Schiavone broke her twice to win the first set. But South fought back bravely to take the second.
The third set went with serve until a fine backhand by South broke Schiavone for 4-3 and she closed out for the win.
"I'm so happy to have won - I can't believe it," said the delighted Wimbledon debutante whose win was watched by tennis great Martina Navratilova.
"I was nervous playing against someone who is 14th in the world, but I had nothing to lose.
"And once I was out there, I loved every minute. I think having some belief in myself was the key."
Borwell lost in round one on her Wimbledon debut last year
Borwell, 26, made a good start in her contest with Domachowska, comfortably taking the first set.
The Middlesbrough-born player, now based in Cheltenham, lost the second on the tie-break.
But she showed her battling qualities in a tight final set, breaking in the 10th game to set up the win.
Borwell said the victories - together with several wins for unheralded British men - was a promising sign.
"It's nice to see a few British names still in the draw - hopefully some of us can progress," she said.
"My main goal is to be British number one and anything else will be a bonus."
She now meets 19th seed Ana Ivanovic of Serbia & Montenegro in the second round.