Nick Kyrgios confessed that he had little more to give physically as his nine-match win streak came to an end in the quarter-finals of the ATP Montreal Masters on Friday.

The Wimbledon runner-up lost 7-6 (7/4), 6-7 (5/7), 6-1 to Polish powerhouse Hubert Hurkacz after coming to the court with 15 victories from his past 16 matches.

But the Australian had little left to give as his body began to complain.

“My body hasn’t been feeling great the last week,” he said. “I was feeling the abdominal (muscle) a little bit before the match. My knees hurt.”

Kyrgios kept the pace of the match brisk as he held his own in the first two sets before finally losing momentum in the third as Hurkacz took control.

The Aussie was annoyed as his opponent left the court for a change of clothes, a delay that ate into his fragile fitness.

“Obviously when you’re playing and you stop for like five to 10 minutes, it doesn’t help your body,” Kyrgios said.

“My body was so stiff after that, I couldn’t move properly.

“I mean, it’s within the rules. I’m not going to complain. I completely stiffened up.”

World number 37 Kyrgios, whose performance this week will send him into a seeded US Open spot, added: “I’m not a machine. I’m a human.”

Kyrgios won his first ATP title in three years last week at Washington and shared the doubles crown with Jack Sock, the first man in the event’s 53-year history to take both crowns in the same year.

“My knees were sore, my back was sore… I was trying to stay moving, but I just stiffened up,” Kyrgios said. “My body hasn’t been feeling great the last week.”

Kyrgios said he needs a pause before returning to the fray next week at Cincinnati in the last major tuneup for the US Open, which begins August 29.

“I feel good, but the US Open still is two and a half weeks away. I have Cincinnati next week. That’s all washI’m focusing on,” Kyrgios said.

“I’m focusing on today, tonight, recovery, food, then just resting, then Cincinnati. That’s where my mind is at.”