Tennis journalist Jon Wertheim has shared his thoughts on Holger Rune and Stefanos Tsitsipas' drop in form at the latter end of the 2023 season, saying that one is far more concerning than the other.

World No. 7 Tsitsipas had a strong start to the 2023 season, reaching the final of the Australian Open in January. However, following his win at the Los Cabos Open in early August, the Greek player had a difficult time on the rest of the North American hardcourt swing.

This has continued into the autumn and through the Asian Swing, with the former World No. 3 having been unable to win back-to-back main draw matches since Los Cabos.

Another Top 10 player who has struggled in recent months is World No. 6 Rune. This summer, he broke into the Top 5 in the ATP Ranking for the first time but experienced a drop in results on the North American swing which culminated in a first-round exit at the US Open.

The Dane then experienced similar disappointment on the Asian swing, with a second-round defeat to Grigor Dimitrov at the China Open and a first-round loss to Brandon Nakashima at the Shanghai Masters. This week, he aimed to defend his title at the Stockholm Open but ended up crashing out in the opening round again.

However, Wertheim said that he believed 20-year-old Rune had simply "hit a wall", whereas Tsitsipas' decline in form was more worrying.

"Holger Rune has simply hit a wall," he said in his piece for Sports Illustrated.

"There is a finite amount of top-tier tennis even the stars can play. Rune is clearly cooked. I would submit that Stefanos Tsitsipas is far more of a concern," he added.

Tsitsipas is currently preparing to compete at the European Open in Antwerp, where he will face Botic van de Zandschulp in the first round. He will be aiming for a deep run here to secure a place at the ATP Finals in Turin, which have looked at risk for him in recent months.