The Dallas Mavericks' impressive offseason comes to a halt after Portland officially matches the offer sheet for Matisse Thybulle.

After the Dallas Mavericks submitted an offer sheet for Matisse Thybulle that could have brought him to Texas, the Portland Trail Blazers matched the deal, keeping him in Portland, at least for now.

For the Mavericks, this is the first hiccup in an otherwise very productive offseason. The Mavericks extended Thybulle a three-year, $33 million offer with a $11.5 million player option in the final year. Thybulle's perimeter defense enticed the Mavericks. With two All-Defensive Team appearances in his first four seasons, there's no denying his prowess on that end of the floor. The Mavs were especially interested since they just parted ways with Reggie Bullock in a three-team deal that brought Grant Williams to Dallas.

Why isn't Matisse Thybulle on the Mavericks?

The Blazers have agreed to match the Mavs' offer sheet for Matisse Thybulle. As a restricted free agent, Thybulle was acquired by Portland from the Sixers in February last season. According to Wojnarowski, the offer sheet was signed and submitted to Portland Thursday morning. Under the new Collective Bargaining Agreement, teams have one day to decide whether to match offer sheets if they are received by noon. ESPN's Bobby Marks details more on that deal below:

The silver lining going forward for Thybulle is that he's done considerably better offensively in Portland compared to Philadelphia. In Philadelphia, he averaged 2.7 points per game. In Portland, Matisse averaged 7.4 points in 22 games as a starter, shooting 43.8 percent from the field and 38.8 percent (a career-best across a season with one team) from deep.

Now, according to Marks, with 13 players under standard contracts, the Blazers are $3.4 million below the luxury tax line. While The Mavs are $9 million below the tax and can still benefit from the non-taxpayer mid-level exception, which starts at $12.4 million next year.

With Thybulle unavailable, expect Dallas to look for another defensive-minded wing.