Isner deals with unexpected loss at ATP Finals in London

John Isner has had a rough time in London, not just on the court. He lost all of his round-robin matches to Novak Djokovic, Marin Cilic and Alexander Zverev in his ATP Finals debut—all in straight sets.

But the 33-year-old has had to deal with incredibly tough news: the unexpected loss of his friend and former strength coach 35-year-old Kyle Steven Morgan.

Isner found out after his loss to Djokovic.

"When I left college, I worked out exclusively with Kyle for probably seven years. That's four, five times a week for seven years,'' Isner said. "We lived together, as well. Certainly very close. It's devastating not just for me, but for a whole bunch of people. He was a fantastic guy."

A lot has changed in Isner's life recently. So much has been made of how Isner will adapt to playing full-time on the ATP tour as a new father. He seems to have embraced it, as he reached the semifinals in Stockholm just weeks after the birth of his daughter, Hunter Grace.

“She may have been watching back home,” Isner said in Stockholm. “I don’t think she’ll remember this match, but I think she was watching with my wife. I’ll see them in a few weeks when I finish up my season.”

Isner season got a little longer when he managed to slide into the ATP Finals field thanks to his No. 10 ranking and Rafael Nadal and Juan Martin del Potro not playing due to injuries.

But his wife, Madison, and daughter came to visit him in London, surely giving him some much-needed support.

Isner ends the season at No. 10 after winning two titles including his biggest one yet in Miami.

This Week on Tennis Channel:

ATP Finals (Sun - Sun 11.11 - 11.18) - Novak Djokovic, Roger Federer and the world's best collide in the season Finale. Live coverage begins on Tennis Channel Sunday at 7:00am EST.