Kyrie Irving accepted the blame for the Dallas Mavericks being 2-0 down to the Boston Celtics and vowed to do "whatever it takes" to turn things around.

The Mavs lost 107-89 in Game 1 of the NBA Finals and followed that up with a 105-98 defeat on Sunday to leave themselves with a mountain to climb.

Luka Doncic felt his performance cost his side in the most recent of those encounters, despite finishing with 32 points, 11 rebounds and 11 assists.

By comparison, fellow superstar Irving registered 16 points, two rebounds and six assists in almost the exact same number of minutes on the court.

And Irving admits it is now on him to step up in Game 3 at American Airlines Center on Wednesday if the Mavs are to drag themselves back into the series.

Asked about a conversation he was seen having with Doncic, Irving said: "It started with me just telling my [brother] I got to play better for him, alongside him.

"In order for us to accomplish our goal, we both have to be playing well and we both have to be doing the little things, doing whatever it takes to win.

"It was an easy conversation. But it started with me reaching out, just letting him know it's my fault, taking accountability for not playing particularly well."

Irving has so far averaged 14 points in the two games with the Celtics, which is down on the 22.8 points he averaged per game in the playoffs.

"First thing of that is just accepting that I haven't played well or up to my standards, as well as I would have liked," Irving said.

"Being back in Boston, there's such a level of desire that I have inside of me to play well. I wanted to be there for my teammates. As a competitor, it's frustrating. 

"But I don't want to let that seep in or spill over to any other decisions I have to make there as a player."

Irving has lost 12 straight games against the Celtics, whom he left in 2019, but Boston coach Joe Mazzulla is aware of what the eight-time NBA All-Star is capable of.

"It's not about shutting him down," Mazzulla said ahead of Game 3. "It's about making it difficult for him because of his ability to impact plays. We just have to fight for that. 

"He's got some good looks. I think we have to guard him better. I think he's definitely going to be more aggressive."