Roger Federer believes he is finally moving through the gears to become “dangerous for anybody” at the Gerry Weber Open.

Back on the grass, the 17-time Grand Slam champion opened his title defence in Halle on Wednesday and was buoyed by his performance as the Swiss continues to find his way back to top form following an injury hampered 2016.

“It was okay. First rounds are always where you don’t play your best usually. You have to find a way. It was hard to find a rhythm against Struff today. He took the ball early, went for a lot on the forehand, backhand, he has a big serve, especially first one,” explained the world No.3, who contained the wild card’s threats and struck a blistering forehand cross court winner on the run to secure a pivotal break in the opening set.

The back complaint that ruled Federer out of Roland Garros seemed to be a distant memory as the 34-year-old glided across the turf and kept a pace in heavy-hitting rallies.

“You go back to basics, you focus on your own serve. I thought I did that very well. He never really had chances on my own serve, so that was comforting. And then on the return I had my chances but he kept going for it.”

Despite a comfortable 6-4, 7-6(3) victory over world No.88 Jan-Lennard Struff, Federer was keen to cool expectations of adding a ninth Halle trophy to his trophy haul.

“The bar is naturally lower overall just because I need to first feel like I’m free with everything, my mind, my body, my game. I’m getting there. I’m happy that I’m getting more and more info every match I play,” added the top seed, who takes on Tunisia’s Malek Jaziri in the last 16.

“Now, I feel after the first round, after having played last week, actually maybe something is really possible here. I don’t want to get too carried away but I feel like if I serve the way I did today and I’m able to step it up just a little bit on the return from the baseline, all of a sudden I’m dangerous for anybody. But I take one match at a time and I hope just to keep on playing a bit better match by match.”

Mercedes Cup champion Dominic Thiem arrived at Halle in the spotlight, having also become only the third Austrian to reach the top 10 in the rankings as a result of his Stuttgart triumph.

“Perhaps the Germans will take an Austrian into their hearts,” joked the 22-year-old moments after a highly efficient first match in Halle.

The crowd certainly warmed to the player with the most victories on Tour in 2016 (now 46) and the only title winner on the trio of grass, clay and hard courts. He is the talk of the town.

“I don’t have any expectations yet, last week was just a dream and I don’t think that will happen again so soon,” insisted Thiem. 

“But obviously I’m very happy about the match today, it’s really tough to play such a good match like that after the nice week in Stuttgart. It was an indoor match, so different conditions, but I’m happy with my service games, I only had trouble once and broke at the right times.”

The world No.7 navigated past Portugal’s Joao Sousa 7-5, 6-4 with relentless precision on serve and formidable force off each groundstroke wing.

The standout factor was that Thiem made 20 forays to the net, with a 65 percent success rate at stealing the point. It’s a facet to his game that the Austrian has been working on ahead of Wimbledon.

“Yeah I think it’s a good thing on grass, to play serve and volley, to come in a couple of times. The bounce here is very low so if you manage to come in you have a good chance of taking the point,” said the third seed. “I think I have improved my volley game, I feel much more comfortable than last year at the net and it’s also fun to use.”

World No.95 Teymuraz Gabashvili stands in his way on Thursday, “He plays very, vest fast and he’s dangerous hitting in his comfort zone. It’s tough on grass to knock him out of that zone rather than on the clay, so it will be very difficult,” added Thiem. “I’ll try to serve well again, the most important factor on the grass, then we will see what happens. If I lose tomorrow, no big deal, but if I win it will be very nice.”

Thiem’s half of the draw has been opened up by the withdrawal of second seed Kei Nishikori, who picked up a rib injury on Monday in the opening round win facing Lucas Pouille.

“I hurt my left side in the first match, and I tried to recover over yesterday and today but I couldn’t hit today. It was too painful,” said the disappointed world No.6, who expects to recover for a full title tilt at SW19.

“It’s very unfortunate. I’ve had this left side injury a couple of times, it’s nothing new but I don’t think it’s going to take too long. I just need a few days to get better.”

In 2015 the Japanese star sustained a calf injury at Halle and also had to withdraw in the semi-finals, an injury which hampered his Wimbledon campaign.

“It’s so frustrating for me, again at this tournament, this is one of the greatest tournaments on grass and Wimbledon is coming up. It’s not easy to withdraw with injury but I’m sure it’s not a big deal.”

The German fans continue to become absorbed by their promising teenager Alexander Zverev.

The towering world No.38 has reached a maiden Halle quarter-final but had to rally from a stuttering start to prevail against countryman Benjamin Becker. Zverev had been on court late on Tuesday in a marathon doubles match with brother Mischa, as the duo edged past veterans Radek Stepanek and Nenad Zimonjic.

“I started off pretty badly, I couldn’t make a first serve, I felt a little slow,” said the teenager, who rapidly fell 1-4 behind. “It had a little bit to do with the doubles yesterday because we gave it our all and it was mentally very, very difficult, 19-17 in the decider. Playing with my brother is special so I was trying my very best.

“He started off very well, he didn’t give me much time on my shots so I was missing a lot when he was rushing me.

“I started to pick up my game and found a way back into the match, deciding not to miss anything, make him win the points. I started to make a lot of returns and hit some first serves at important moments. It could have easily been 5-2 down so luckily I won the first set and unfortunately he had to retire with back spasms.”

Having left the Centre Court a 7-5, 3-0 victor to booming applause, the youngster declared he can handle the pressure of being his nation’s finest prospect.

“Of course everyone is waiting for the next Boris Becker. But it’s also nice to have that much attention. I find that’s something positive.”

Dustin Brown, who has been awarded a wildcard for the upcoming Wimbledon Championships, fell 7-5, 7-6(8) to the mastery of rejuvenated Marcos Baghdatis, who earned a clash with Zverev in the final eight.

Americans Mike and Bob Bryan cruised into the semi-finals of the doubles with an emphatic 6-3, 6-2 triumph over Tomas Berdych and Marcel Granollers.

The twins next will face the Zverev brothers or Raven Klassen and Rajeev Ram in the final four.