Sam Querrey up 4-3 in fourth set

Sam Querrey continues to battle and has a 4-3 lead in the fourth set against Stanislas Wawrinka.

Wawrinka leads the fourth-round match, 7-6, 6-7, 7-5.

Both players are vying for their first appearances in a Grand Slam quarterfinal.

UPDATE (4:40): Querrey is now up 5-3. Wawrinka is serving to stay alive in the set.

UPDATE (4:52): Querrey can't close it. Wawrinka pulls to within 5-4 in the fourth set.