Roger Federer's former coach Ivan Ljubicic has shared his thoughts on which ATP players could lift the trophy at the upcoming US Open.

Former top-10-ranked player Ljubicic coached tennis legend Federer from 2016 until his retirement in 2022. While working with the Croatian coach, the Swiss player won his last three Grand Slam titles, two at the Australian Open and one at Wimbledon.

Now, the 44-year-old has given his opinion on the players in contention to win the men's singles event at the upcoming US Open, starting on August 28.

In an interview with Oasport, Ljubicic said that world No. 6 Jannik Sinner is in with a good chance following his victory at the National Bank Canadian Open in Toronto last week, the 21-year-old's first ATP Masters 1000 title.

"Jannik Sinner has the mentality of a champion, this victory is important and it tastes like liberation for him," Ljubicic said, highlighting that defeating world No. 12 Alex de Minaur in the final was no easy feat.

"Against De Minaur wasn't easy, he's a difficult tennis player to face and we're talking about someone who makes you play badly," he added.

"Sinner can fight for victory at the US Open, he is one of those four players who stand apart from others in the Race," he continued.

The other three contenders according to Ljubicic are Carlos Alcaraz, Novak Djokovic, and Daniil Medvedev, who are currently ranked 1, 2, and 3, respectively. Alcaraz recently defeated Djokovic at Wimbledon, a major that the Serb had won four times in a row prior to this year and seven times overall.

Meanwhile, Djokovic emerged victorious at this year's Australian Open and Roland Garros, bringing his Grand Slam total to a record-breaking 23. Medvedev won the US Open back in 2021, and won three consecutive ATP titles earlier this year in Rotterdam, Doha and Dubai.

Other strong contenders are world No. 4 Stefanos Tsitsipas and No. 5 Holger Rune. However, as players near the last Grand Slam of the year, there is a chance that anything could happen.