Clarke has appeared in five games, averaging 14.6 points and 8.6 rebounds per game, including his 23 points and 14 rebounds in Sunday's overtime win over the New Orleans Pelicans.
The Grizzlies are 5-1 so far in Vegas and will take on the Minnesota Timberwolves in the Summer League final Monday night.
This run is even more impressive considering second overall pick Ja Morant wasn't on the roster.
Clarke, the No. 21 overall pick in the 2019 draft, enters the league with high expectations after a breakout 2018-19 season with Gonzaga. He will join Morant, Jaren Jackson Jr. and others in a promising young core for Memphis.
Meanwhile, the Grizzlies also have other previous Summer League MVPs on the roster, including Kyle Anderson (2015) and Jonas Valanciunas (2013).
This award has been somewhat of a mixed bag in recent years between future stars and flash-in-the-pan prospects.
John Wall (2010) and Blake Griffin (2009) were both named MVP of the Summer League, while Damian Lillard was named co-MVP in 2012. On the other hand, Josh Selby was the other co-MVP that season, while Glen Rice Jr. (2014) also had a forgettable NBA career.
The Los Angeles Lakers had back-to-back winners the past two years in Josh Hart and Lonzo Ball, but now both are with the New Orleans Pelicans.
Memphis will hope Clarke can continue the type of production he showed over the past couple of weeks.