World number three Dominic Thiem says tennis players "must learn" from the ill-fated Adria Tour and described Nick Kyrgios' criticism of those who took part as "unnecessary".
Thiem played in the Belgrade leg of last month's ill-fated tournament organised by world number one Novak Djokovic.
"We have to learn from the mistakes and be careful nowadays with this pandemic we are facing. That's what we have to take from the Adria Tour," Thiem said at an exhibition tournament in Berlin.
Djokovic, Grigor Dimitrov, Borna Coric and Viktor Troicki all then tested positive for Covid-19.
Djokovic later apologised for the event where players embraced across the net and later partied together at a nightclub.
Thiem tested negative for the virus but, like all those involved, faced fierce criticism and has already apologised.
"Novak and the others didn't commit any crimes, you have to make that point," Thiem added.
"The fact we were criticised is not unfair because we all made mistakes. That's clear. But it was way too much at the end, because the whole tournament was well intended."
Kyrgios has been highly critical of anyone who played in the Adria Tour, which he branded a "boneheaded decision" to hold with such little regard for hygiene.
Meanwhile, Katie Boulter believes top-level tennis could benefit from some of the innovations used in recent exhibition events.
Players donned headsets to talk to TV commentators during changeovers in last month's Battle of the Brits men's event.
While Boulter admitted issues with possible distractions in tournament play, the 23-year-old conceded the sport should be looking at new initiatives.
Boulter will take on Alice Gillan as The Progress Tour Women's Championships get under way at the LTA's National Tennis Centre today.
Asked about tennis' recent innovations, she said: "I thought it was fresh and interesting, some of the stuff they did, and maybe we can bring it onto the tour.
"But some of it is quite hard to do - having the headsets on court is quite interesting but, at the same time, when you're really in that match and it's not an exhibition, I'm not sure how you're going to react to it."