Milos Raonic was unable to celebrate his return to the ATP Tour with a title as Marin Cilic pipped him to the Istanbul Open crown in Turkey.

Raonic had played only one match since February prior to arriving in Istanbul because of a hamstring problem but found form straight away on the clay.

However, it was Cilic who proved just the stronger in the title decider, winning the opening set on a tie-break and then securing the only break of serve in the second to triumph 7-6 (7/3) 6-3.

Raonic had his chances, creating seven break points in the match, but Cilic saved all of them, helped by nine aces.

At the BMW Open in Munich, 20-year-old Alexander Zverev won his third ATP title and his first on home soil.

The German, ranked 20th, came from a break down in the opening set to defeat Argentinian qualifier Guido Pella 6-4, 6-3.

Maria Sharapova, meanwhile, set up a grudge match against Eugenie Bouchard as she continued her return from a drugs ban with a first-round win at the Madrid Open.

Sharapova's three-set triumph over Mirjana Lucic-Baroni means she will next meet the Canadian, who branded Sharapova a "cheater" prior to her return to competitive action.

Bouchard, who won her first-round match against Alize Cornet on Saturday, said she believed the Russian should have been banned for life rather then the 15-month sentence she served for taking meldonium.

She told reporters last month: "She's a cheater and I don't think a cheater in any sport should be allowed to play that sport again

"It's so unfair to all the other players who do it the right way and are true. [She's] definitely not someone I can look up to any more."

Sharapova beat Lucic-Baroni 4-6, 6-4, 6-0 in her second tournament back after making the semi-finals on her return in Stuttgart last month.

Johanna Konta's struggles on clay continued as she exited the Madrid Open in the first round after a third-set capitulation against Laura Siegemund.

Konta, the tournament's sixth seed, was 3-0 up in the decider, but the in-form German rattled off five games in a row to steal a 3-6 7-5 6-4 win that finished at 2.17am local time.

The British No.1 has become a real force on the women's tour over the last 18 months but that is yet to translate to the clay as she has won just three games on the surface in her career.

There was a clear chance to make that four against a tough opponent in Siegemund, who won in Stuttgart last week in a strong field that included Angelique Kerber, Simona Halep, Konta and Maria Sharapova.

It started well as Konta claimed the first set with two breaks and looked on course for a straight-sets win when leading 5-4 in the second.

But Siegemund upped her game when it mattered, breaking Konta either side of two clutch holds to send it into a decider.

It looked like the world number seven had found a way to win it when she surged into a 3-0 lead but Siegemund again recovered with five successive games, fighting back from 0-40 down in one of them, to claim an impressive win.