Oddsmakers are predicting a close series between the Thunder and Mavericks.
The Thunder opened the series as early favorites, winning -122 at FanDuel Sportsbook and advancing to the Western Conference Finals.
After eliminating the Clippers in the first round on Friday night, the Mavericks are +100 before defeating Oklahoma City.
Las Vegas bookmakers also expect this series to last a long time.
FanDuel has a game over/under of 5.5 for the series, but the over (-180) has a decent chance, indicating the sportsbook expects it to last six to seven games.
This is arguably the tightest series spread of any semifinal round. The Knicks and Nuggets are heavy favorites heading into the matchup against the Pacers and Timberwolves, respectively, and the Celtics are almost certainly an even bigger favorite against the winner of Cavaliers vs. Magic.
Oklahoma City wore Dallas' number during the regular season and went 3-1 in four games, but only one of those games featured a healthy Luka Doncic and Kyrie Irving.
Both teams are in the second tier of title contenders as the NBA enters the second round of the playoffs.
The Thunder, who became the youngest No. 1 seed in NBA history with 57 wins in the regular season, have the third-best odds to win (+850).
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The Mavericks are one spot lower at +1000, tied for fourth on FanDuel's board with the Timberwolves and Knicks.
The Celtics (+120) and Nuggets (+300), who were Finals contenders before the season even started, remain by far the favorites in terms of title chances.
The Thunder and Mavericks tip off in Oklahoma City on Tuesday at 9:30pm ET on TNT.
