AceShowbiz - Maria Sharapova and Alexander Gilkes heated up their summer vacation. The tennis ace's millionaire boyfriend showed his love and admiration for her and her body in the most physical way possible while they're relaxing in Positano, Campania, Italy on Sunday, July 22.

In some photos obtained by TMZ, the Russian athlete was sunbathing in a two-piece black bikini, flaunting her perfect curves, and her boyfriend couldn't resist the temptation to have a taste of it. Alexander planted his face on her bare butt as he appeared to playfully bite her perky derriere while the 31-year-old beauty was lying on a lounge chair and checking at something on her smart phone.

Alexander also got handsy, rubbing his girlfriend's booty while lying on another chair next to her. At one point, he was seen moving to Maria's chair and getting down on his hands and his knees on top of his girlfriend.

Maria, who completed her look with a straw hat, took off her bikini top to minimize her tan lines. The couple enjoyed champagne while soaking up the sun.

Maria returned to the WTA tour in April 2017 after a 15-month ban for using Meldonium. The former world No. 1, however, has had difficult years so far, losing in Wimbledon first round for the first time in her career when she was sent home by Vitalia Diatchenko earlier this month. "Sometimes, you put yourself in a better or winning position, and you don't finish," Maria commented on her loss.

Her former coach Javier Capitaine recently claimed that Maria wasn't using steroid. "It was a mistake, she wasn't using a steroid or something strange. Of course, she has to be responsible for the consequences. Maria is humble and an incredible worker," the tennis coach, who worked with Maria in the past, told Times of India.

Maria, meanwhile, has announced that she wouldn't compete in the Mubadala Silicon Valley Classic that takes place at San Jose State University from July 30 to August 5. She said in a statement, "I am really sorry to have to miss the event in San Jose this year. I have heard amazing things and I know all the girls are excited to come to play. Unfortunately, I have been forced to make some very tough decisions at this point in my career when it comes to my tournament schedule. ‎I need to take care of my body and make sure I stay healthy. I look forward to coming to play next year."