If the Celtics decide to go all in on winning a banner or two and then blowing it up, Giannis for Tatum could work, salary wise. The Celtics don’t have to wait for Tatum to fully recover and avoid the risk of Tatum losing a step due to the injury. Beyond that, Giannis has always been better than Tatum. The big downside is that Giannis is a few years older and has played a lot more professional games.