In completely expected news, the Celtics have officially exercised the $9.9 million fourth-year team option on forward Jayson Tatum, according to The Athletic's Shams Charania.

The Boston Celtics have exercised forward Jayson Tatum's $9.9M fourth-year team option, league sources tell @TheAthleticNBA @Stadium. Critical third season coming for Tatum.

— Shams Charania (@ShamsCharania) October 14, 2019

Drafted with the No. 3 overall pick in 2017, the 21-year-old Tatum is coming off a sophomore season that came with a slight step back from the strides Tatum made in the 2018 NBA Playoffs, as Tatum struggled to find his game in a crowded Boston roster construct and experienced a six-percent drop in his three-point efficiency from his rookie season.

Despite those struggles to find his game and emerge as a star, Tatum still set a new career-high across the board, though, with 15.7 points, 2.1 assists, and six rebounds per game in 2018-19.

As noted by Charania, this will be a hugely important year for the 6-foot-8 wing, as the Celtics surely want him to emerge as a foundational piece of their franchise alongside new free agent addition Kemba Walker and fellow lottery pick Jaylen Brown.

With Tatum's fourth-year exercised, Tatum is now eligible to sign an extension with Boston next summer.