Boris Becker thinks Novak Djokovic’s free-fall began when he captured the elusive french open crown last year. The former mentor was once again critical of Djokovic’s form following another early round exit at Monte Carlo Masters.

Djokovic fell victim to Belgium’s rising star David Goffin 6-2, 3-6, 7-5 in the quarter-finals of the Monte-Carlo Masters. However, Nole’s latest loss wasn’t as shocking as his previous early round exits this season because of the subpar form he showed in the first two rounds (Giles Simon and Pablo Carreno Busta both pushed him to the third set) prior to his elimination.

For Becker, who worked for three years with Djokovic, seeing his former student struggling against players not named Roger Federer, Rafael Nadal or Andy Murray is an alarming sign that the Serb is not in tip-top condition, both physically and mentally. He knows that Djokovic’s woes all began at the 2016 French Open, where he fulfilled the dream of becoming a career Grand Slam champion.

“I think a lot has changed for him winning the Grand Slam last year at the French - it was his lifelong dream, and then you pop the balloon and the air went out and he hasn't got the air back,” Becker said in an interview with Sky Sports.

Questioning Nole’s work ethic

Even when he was still part of Djokovic’s coaching team, Becker never backed down from openly criticizing the Serb for his lack of motivation in training.

The German tennis legend felt his student all of a sudden lost all the passion for the sport that catapulted to the top of the tennis world in the past 3 to 4 years. ESPN Tennis writer Peter Bodo also questions Djokovic’s work ethic in his recent article, after noticing the Serb gasping for air deep into his quarterfinal match with Goffin.

“Friday, the focus was again on his suffering game. It was the legs and lungs that let down Djokovic in his Monte Carlo Masters quarterfinal with David Goffin,” said Bodo, who believes the Serb’s game completely fell apart since his split with Becker.

It’s not too late to right the ship

Despite his lack of form as of late, Becker is still confident the former world’s no.1 will find his groove back at some point as long as he continues to work hard .

At 29, Nole is pretty much at the prime of his career to refocus and reignite another run. The 12-time Grand Slam winner is scheduled to play at Madrid and Rome before defending his crown at the French Open late May.