Roger Federer believes his lack of practice time is to blame for a couple of ragged performances at the Gerry Weber Open, but he is satisfied heading into the final against Borna Coric.

World number one Federer is one match away from a 10th Halle title, a result that would ensure he remains at the top of the rankings when they are updated next week.

But the Swiss great has struggled at times in his run to Sunday's showpiece, again made to work hard as he downed Denis Kudla 7-6 (7-1) 7-5 in the last four.

Federer insists this is to be expected, though, after sitting out the clay-court season and then returning to play two tournaments in two weeks on grass.

"I'm playing a lot of matches right now. I'm missing practice a little bit, but it's OK, it's part of the game," he said. "I'm in back-to-back grass court tournament finals, so I'm actually very happy.

"I'm just hoping to play another good match in the final. The finals are always where I want to play my best, where I'm going to judge my performance, at the very end.

"Then I will have time to rest, to practice and to get ready for Wimbledon."

Federer will place Coric after Roberto Bautista Agut retired early in the first set of the other semi-final, with the score 3-2 to the Spaniard with no break.

Coric knocked out second seed Alexander Zverev earlier in the competition.