Andy Murray's marathon second-set tie-break with Philipp Kohlschreiber was a first for the world number one in what he described as "special match".

The opening set of the Dubai Tennis Championships quarter-final went the way of Kohlschreiber and the German had more than one opportunity to seal a surprise win.

In the second set Kohlschreiber saved one set point ahead of the breaker, and wasted another six as Murray levelled.

It took over 30 minutes to find a winner in the second set tie-break as momentum swung both ways, Murray producing some sublime drop shots, while Kohlschreiber repeatedly found the line with his groundstrokes.

Eventually it went Murray's way 20-18, the sixth time a breaker has gone to 38 points since 1991.

"I have never played a tie-break that long ever. I'll probably never play another one like that again," said Murray.

"I mean, I have been playing on the tour for 11, 12 years now, and nothing's been close to that.

"There was definitely some unbelievable points in that second-set tie-break.  We both missed a couple of shots, but in general, I think the level was extremely high.

"It's a special match to win because of how it went."