I can see Thiem, Zverev, Medvedev or Tsitsipas getting the better of Novak. Id be amazed it either he or Rafa got into the final. Finally changing of the guard time for me watching all these guys.
Certainly I feel the current rankings don't lie in showing a big gap after the top 7 ( the traditional big 3 and these 4 names ) and then a further big gap after #8 Rublev ( the other player who might consistently seriously compete in the next year or two ) to #9 Schwartzman.
In the short term I still wouldn't rule out Djoko or Nadal here, or Djoko's next opponent, Raonic.
Karatsev had a remarkable run in the Czech
Republic after last years USO. He reached the final of the large Prague Challenger losing to Stan. He then won Prague 2 , the week after and Ostrava the week after that for a 16-1 record, before slipping into a so so run through the European indoor season. With AO qualies, hes now 8-0 in 2021.
Mike Dickson in the Mail on Sunday points out that Cam's defeat marked the 8th out in the last 11 Grand Slams in which no Brit has made the second week of the singles. The 3 in question are all Johanna Konta in 2019 and the last British man to reach the last 16 was Kyle Edmunds' -semi final at the 2018 AO. He does add that the AO should prove a building block for Cam.