Alexander Zverev successfully defended his BMW Open title on Sunday with a straight-sets win over fellow German Philipp Kohlschreiber in Munich.
Zverev converted four of his six break point chances to polish off a 6-3 6-3 triumph in just 71 minutes for a seventh Tour title of his career.
Victory continued the world number three's recent strong run of form, which included reaching the semi-final of the Monte Carlo Masters.
Zverev told atptour.com: "I had to play my best tennis to have a chance, and that is what I did. I found my rhythm and felt very good on court."
Joao Sousa became the first Portuguese player to win the Estoril Open title after a popular 6-4 6-4 final win over American Frances Tiafoe.
Sousa broke his opponent four times on his way to a comfortable victory which marked his third tour-level title, and his first since 2015.
Sousa, who became the first home player to win in 29 years of the tournament, sunk to the clay in tears upon his moment of triumph.
Japan's Taro Daniel continued his rise up the rankings by winning his first tour title at the Istanbul Open.
Daniel beat another final debutant, Malek Jaziri of Tunisia, 7-6 (7/4) 6-4 to continue an impressive run which also saw victory over Novak Djokovic at Indian Wells.
The 25-year-old wasted two match points when leading 5-3 in the second set but recovered his poise to finally claim victory at his fourth attempt in the following game.
In the first round of the Madrid Open, 14th seed Tomas Berdych fell 6-4 6-2 to French veteran Richard Gasquet, while Denis Shapovalov beat Tennys Sandgren of the US 6-1 6-4.