World number three Alexander Zverev got his clay court season back on track with a 6-4, 6-1 over Frenchman Alexandre Muller in the first round of the ATP event in Munich on Monday.
The German came into the Munich tournament having lost his opener at last week's Monte Carlo Masters to Italian Matteo Berrettini, missing the chance to bump Jannik Sinner from the world the No 1 position.
Instead, that defeat and the Carlos Alcaraz's victory in the final on Sunday saw Zverev dropping down a place in the rankings and dented his preparations ahead of next month's French Open.
Zverev broke his opponent in the first game but Muller broke back at 3-3 before Zverev recovered to win the set in 47 minutes.
The number one seed found his rhythm in the second, breaking his opponent three times.
The 27-year-old completed victory in one hour and 20 minutes.
Clay-court specialist Zverev has played six tournaments since losing the Australian Open final in three sets to Sinner in January, but has not made it past the quarter-finals at any.
Since winning back-to-back titles in Munich in 2017 and 2018, Zverev has not made it past the final eight.
He will face either countryman Daniel Altmaier or Taiwan's Tseng Chun-hsin in the quarter-finals.
Earlier on Monday, world number 15 Ben Shelton endured a stuttering start to the tournament, coming from a set down to beat world number 410 Borna Gojo 4-6, 7-6 (8/6), 7-6 (7-3).
Shelton, seeded second in Munich, fought off three match points, winning both of his sets via tiebreak in two hours and 24 minutes.
Defending champion Jan-Lennard Struff, who beat American Taylor Fritz in the final last season, opens his campaign against Argentinian Francisco Cerundolo on Tuesday.
Meanwhile, world number two Carlos Alcaraz took aim at his critics on Monday after winning the Monte Carlo Masters at the weekend.
The 21-year-old is gearing up for his French Open title defence next month but has struggled for consistency at times this year, including suffering an early exit at the Miami Open in March.
The four-time Grand Slam winner continues his clay court preparation this week at the Barcelona Open, where he is aiming for a third triumph.
"It is true that perhaps there have been results that have not been enough for some people, even for myself," Alcaraz told reporters in the Catalan capital.
"I've reached a point where no defeat is just nothing but (instead) it is a learning process, and we have to move forward.
"It is easy and free to talk, when someone has an expectation that is not met. It is very easy to talk, that is what I can say."
Alcaraz, who had to come from a set down to beat Lorenzo Musetti in the Monte Carlo final, admits he is not at his best and is looking to improve his form.
"I can say that in Monte Carlo I gained a lot of confidence," Alcaraz told reporters ahead of his round of 32 match against the American Ethan Quinn on Tuesday.
"I honestly didn't expect to win that title, instead just to pick up rhythm, play matches, add more hours on the clay.
"I don't think that I am at my best level, I think I've played at a better level this year (at other points)," he continued.
"I have played better matches than those in Monte Carlo. It is one thing to win, another to really feel you played well.
"The truth is I think I'm having a good year. Maybe the last month has been a bit worse but I think having a good year."
Alcaraz's idol Rafael Nadal is the player who has the most Barcelona Open titles with 12.
The Spanish superstar retired from tennis at the Davis Cup last November but Alcaraz said the sport still had a bright future.
"I think tennis is in a very good moment right now, in the sense that there are many young players capable of winning big titles and fighting for great things," he added.
"There's a very wide range of players who can do great things.
"We young players are showing strength that we can fight for great things, and that's great for the world of tennis."
Agencies