Teenager Shapovalov smashed a ball in frustration in the deciding rubber of Canada's Davis Cup tie with Great Britain.

Gabas was taken to Ottawa General Hospital for precautionary checks.

He received no major damage but says things could have been very different.

"I came off the court looking like Rocky Balboa,” Gabas said.

"The video is quite shocking to look at. We have to avoid some balls during the season but this one I had no chance.

"I feel quite lucky it wasn't worse.

"Players can be a bit crazy these days. I could see he was angry and that something was coming but I never thought he would hit me."

Shapovalov immediately apologised but was disqualified and later fined $US7,000 ($A9,122) by the International Tennis Federation.