It always amused me that fans put up such a big stink about "the wrestler" appearing in an episode of Star Trek. "The wrestler" happened to be The Rock, who went on to become an enduring box office star, Dwayne Johnson. Obviously there was a certain amount of prejudice going on in these views. "Tsunkatse" on one level is only another version of "Arena," and Johnson is more or less the episode's version of a Gorn, just an opponent for the featured series regular (in this case Seven) to combat. There's very little for Johnson to actually do in an acting capacity. Not that he would have embarrassed himself otherwise.
He's not even the only noted guest star in the episode. Jeffrey Combs and J.G. Hertzler, beloved character actors who'd been featured in Deep Space Nine, made their first franchise appearances since the end of that series nearly a year earlier (both would return in Enterprise, Combs in a featured recurring role). That alone makes this episode notable for me. Hertzler plays a captive Hirogen, the first seen in the series since the fourth season, in a scenario that echoes how his Klingon warrior in DS9 was discovered by Worf.
About the only element about this episode that isn't essential is Seven's role in it. She's a pretty random character to have been featured (in many ways, it would have made much more sense for it to be Chakotay), but there's a nifty new outfit for her in it, if you keep track of that sort of thing.
Otherwise, disregard what you may previously have heard about this one. Just watch it.
franchise * series * essential * character
Memory Alpha summary.