Thomas Frank has revealed that James Maddison has suffered "what looks like a bad injury" after being stretchered off during their pre-season friendly against Newcastle United.

Brennan Johnson had given Spurs a fourth-minute lead, but Harvey Barnes restored parity before the break with neither side able to find a winner in what was Son Heung-min's final match for the club.

And in the 83rd minute, Maddison looked like he jarred his knee during an attempted tackle and immediately limped to the sidelines, gesturing to the bench.

He was carried off shortly after and now looks to be a serious doubt for Spurs' clash against Paris Saint-Germain in the Super Cup, which takes place on August 13, and the start of their Premier League campaign.

Maddison missed the end of last season, including the Europa League final, with a knee injury, and Frank says the 28-year-old appears to have suffered a similar issue.

"Sometimes in life and football, things can be both beautiful and brutal," said Frank.

"That's what we got today. It looks like with Madders a bad injury and then, on the other hand, unbelievable scenes for Son from his team-mates and the respect from the Newcastle players.

"We're pretty sure it was the same knee he injured before."

Meanwhile, Son was applauded off the field by both sets of players as he made an emotional exit in the 65th minute at the Seoul World Cup Stadium, and went down the tunnel in tears following the full-time whistle.

He announced on Saturday that he would be leaving the club after 10 years and is reportedly in talks over a move to Los Angeles FC in MLS.