Blatt and Mirotic faced each other multiple times in the Euroleague, with Blatt coaching Israel's Maccabi Tel Aviv and Mirotic playing for Spanish club Real Madrid.
Blatt said the Montenegrin will be able to make an impact right away and that Mirotic's versatility will allow his game to translate well to the NBA.
"He was a [matchup nightmare] in Europe," Blatt said. "That will be interesting to see, how [Tom Thibodeau] decides to play him. I can't speak to that piece. But physically and athletically and skills-wise, he can swing between positions and take advantage of mismatches."
Thibodeau hasn't committed to how he will use Mirotic, other than to say at the introductory news conference that he envisions Mirotic guarding strictly power and small forwards.
Blatt and Mirotic last crossed paths in the Euroleague championship, when Blatt led Maccabi to a victory.
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