Novak Djokovic beat Donald Young 6-2, 7-6 and advance to the semifinals at the Eastbourne International.
Djokovic saved two set points, on Young's serve at 5-4 and on his own serve in the tiebreaker, and clinched victory with a return winner.
He will next play Daniil Medvedev, who upset fourth-seeded Steve Johnson 6-3, 2-6, 6-3.
"I enjoyed it, especially in the second set," said Djokovic. "The first set went my way and I played well. I felt good on the court and had some break point opportunities early in the second set... I think Donald started playing with less unforced errors, playing with more variety and using his forehand very well from all over the court.
"He served for the set, had a set point and then had set point in the tie-break. It was very close second set. Obviously, it could have gone easily his way. But it hasn't, and I'm just glad the way I kind of held my composure, my nerves. This is the kind of match situations that I was looking forward to having, and I'm glad it happened today and I managed to overcome that."
Gael Monfils scored a 6-3, 6-2 win over wild card Cameron Norrie, striking eight aces and losing just five of his first service points, for a place in the quarter-finals. Monfils will now challenge Bernard Tomic, who defeated Mischa Zverev 6-3, 6-2 in 51 minutes.
Richard Gasquet saved all three break points he faced to beat Kevin Anderson 6-4, 6-4 and now faces John Isner, a 3-6, 7-6, 7-6 Victor over Dusan Lajovic.
