The championship series pits Brown's Orlando Magic against Waters' Los Angeles Lakers, whose victory last night gave them a 2-0 advantage in the best-of-seven series.
"The only reason I'm here with you this evening, Corrine, is to bring my condolences," Waters said in the awkward-but-endearing video, prompting a laugh from Brown.
The Florida congresswoman, in turn, vowed that "there will be no sweep."
"Both teams are great, but in the end it will be the Magic," she said.
"Who have you got?" Waters retorted, showing off her Lakers jersey. "I've got Kobe [Bryant]…you don't have anybody to match that."
Brown responded, "we have a whole a team. You've just got one player." That prompted Waters to talk approvingly about center Pau Gasol ("he is bad") and the rest of the Lakers' squad.
Watch the video – which was posted between games one and two – below: