Eugenie Bouchard will be coached by Marko Dragic at the Rogers Cup after the Canadian split with Sam Sumyk following a disappointing run of results in 2015.
After being named the most improved player on the WTA circuit in 2014 having reached a ranking of seventh in the world, Bouchard has suffered a string of first round defeats this year which saw her drop to 26th on the latest world rankings.
Last year, she reached the last four of three of the four grand slams, including the final at Wimbledon, under former coach Nick Saviano, but after roping in Sumyk at the start of the year, Bouchard has lost 12 of her last 14 matches.
"I just feel like I haven't been quite myself, my confident, aggressive game lately, and that's something that I've been working on very hard in practice," Bouchard said at a news conference Friday.
"I have the belief, and I know my skills are still there and nothing can just vanish. It's just about working hard to getting back on track."
For the time being, Bouchard's partnership with Dragic will only be in place for the US Open tune-up and the 21-year-old confirmed that she has not made a decision on who will be her next full-time coach.
"I'm looking for someone who can help me improve all areas of my game," she added.
"I think it's very important to be able to address the technical side, the tactical side, the mental side and the physical side."