The news just keeps getting worse for the Dallas Mavericks.

Not only is the team mired in the longest losing streak to start a season in franchise history, the Mavs are going to be without Dirk Nowitzki for the foreseeable future.

The sixth-leading scorer in NBA history is being shut down due to right Achilles soreness. The initial thought is Nowitzki is going to miss at least a week before being reevaluated.

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The team is not putting a timetable on his absence. The Mavericks face the Milwaukee Bucks at American Airlines Center on Sunday.

"Is it bad news? Yes. It's bad news, but we'll get through it," Dallas coach Rick Carlisle said. "We'll get through it. We've gone through some periods like this before, but his health is the most important thing.

"He's more than willing to continue playing, but it's pretty obvious that things just aren't right. We've got to do the right thing here and back him off, get to the root of it and get it fixed."

Nowitzki played only 16 first-half minutes in Friday's 105-95 home loss to Portland, dropping the Mavericks to 0-5. No team in club annals had ever started worse than 0-4.

Nowitzki missed two games before suiting up against Utah and the Trail Blazers. The rest initially helped, but he didn't come out of the locker room after halftime Friday.

"It felt better after a couple of days of not doing anything," Nowitzki said. "But as soon as I got back out there with the cutting and the showing and the quick changing of direction, it went right back to feeling the same.

"I'm already not moving great at 38 as it is and to be out there on one leg is not helping myself or the team at all. We are going to get this thing right in the next few days and then ramp it back up."

The Bucks (4-2) extended their winning streak to three with Saturday night's 117-91 home rout over to Sacramento. Mirza Teletovic knocked down seven 3-pointers and led Milwaukee with 22 points off the bench.

Jabari Parker scored 19 and Giannis Antetokounmpo added 17 points. None of the starters played in the fourth quarter.

"Getting able to get some rest in the fourth quarter is a great feeling going to Dallas with fresh legs," said Antetokounmpo, the team leader in scoring, rebounding, assists and blocks.

Coming to Dallas serves as a pseudo-homecoming for coach Jason Kidd, who was drafted by the Mavericks before returning years later to help lead the franchise to its first NBA championship in 2011.

The game is also Jason Terry's first in Dallas as a member of the Bucks. Terry was also part of the championship team during his eight-run with the Mavs and remains a fan favorite.

The Bucks snapped a six-game losing streak against Dallas last season. The Mavs have won three straight in the series at home and 11 of the last 13.