J.J. Barea is learning on the fly.

He's learning to hold the fort while Devin Harris is sidelined. He's learning that he can lead the Mavericks, and they will follow. And he's even learning that he can play a little defense.

Before this season is over, the diminutive point guard probably will learn whether he's a legitimate No. 2 point guard on a good NBA team.

That's a question the Mavericks need answered. They must find out whether they are comfortable using Barea in an important playoff situation if Harris has foul trouble or has to leave the game for any reason.

That's why this trial run of starting the 5-11 Puerto Rican while Harris is injured is an important stretch for Barea and the team.

"That's where we're trying to get him, where he can be a rotation guy," coach Avery Johnson said Thursday. "Not [to put him in] when we're up by 30 or down big, and we throw him in the game and the fans go crazy. We need him to have a significant role now.

"We're trying to get him to the point where, 'Hey, you're the guy.' No added amount of pressure, you don't have to go out and necessarily win the game for us. But if he plays similarly to the way he played [Wednesday night], then he can help us."

Barea had 13 points, four assists and no turnovers in 20 minutes against Milwaukee. He helped the Mavericks jump to a 20-12 lead before he was lifted for Jason Terry.

For Barea, these are heady times. He is getting a chance to earn the faith of not only teammates and his coach, but the entire league.

Look no further than Brandon Bass to realize that other teams are always watching players near the end of the bench who show signs of becoming full-time contributors.

"I thought I could do what I'm doing," Barea said. "With a team like this and a coach like this, it makes it a lot easier.

LOUIS DeLUCA / DMN

Undrafted after his college career, J.J. Barea was signed as a free agent by the Mavericks.

"I'm always looking for the best. I want to be a starter. But I'm realistic, too. I could be a great backup for a couple years. If I keep doing what I'm doing – not turning the ball over and getting better on defense – I think I will [be in the rotation].

"I have great teammates, and it's nice to feel that if you run, they run, and if you walk, they walk. It's like the coach said, it starts with the point guard, like in football, it starts with the quarterback."

Barea's journey to this point is unique. Born in a rural part of Puerto Rico, his family moved to San Juan, and because of Barea's basketball abilities, the decision was made to send him to Miami Christian High School in Miami for his senior season. He gave up baseball (he was a leadoff hitter and second baseman).

"My favorite player was Juan Gonzalez," Barea said. "Then I moved on to Pudge [Ivan Rodriguez]. He's still my favorite."

Barea played in Miami with four other Puerto Ricans in the starting lineup on a team that finished 38-2 and was No. 6 in a national poll. All five players went to Division I schools, with Barea going to Northeastern.

Going undrafted after his college career, Barea was signed as a free agent by the Mavericks. This is his second season, which is about the maximum window any undrafted player gets to prove he can stick in the league.

Since Barea joined the Mavericks, it's been a constant struggle to improve his defense and earn playing time.

Lately, his increased role has opened some doors that may not have otherwise been there. He's getting recognized in restaurants and just about any time he's out and about.

"People start looking at me weird, like, 'Is that him? Is that him?' " Barea said. "They got to look at me a couple times. I look like anybody else in any place."

Some people still don't believe it when he tells them he's a basketball player for the Mavericks.

But slowly, he's starting to get noticed – most importantly by the Mavericks.