The Milwaukee Bucks came into Monday night's matchup with the Washington Wizards hoping to take care of business against one of the league's worst teams, but instead they dropped a frustrating 129-126 game at Capital One Arena.

The loss dropped Milwaukee to 9-13 on the season, and to make matters worse, the Bucks lost starting point guard Kevin Porter Jr. to a lower back injury late in the fourth quarter.

Kevin Porter Jr. Addresses His Back Injury

After the game, Porter Jr. spoke about what led to him leaving the contest with lower back spasms and gave fans hope that the injury won't keep him out for long.

"Last game back I felt a little something in my lower back, but just thought it was soreness coming back but I think it's my body still trying to ramp up...I should be ready by our next game."

Porter exited the game with 6:37 remaining in the fourth quarter after appearing to be in discomfort following a defensive possession, which prompted head coach Doc Rivers to call a timeout.

He was removed from the game and replaced by Ryan Rollins, and the Bucks announced shortly after that he would not return due to lower back spasms.

The timing of the injury was especially tough to swallow because Porter was putting together one of his best performances in a Bucks uniform.

He finished with 30 points on a blistering 12-of-15 shooting from the floor, including 5-of-6 from beyond the arc, while adding five assists, four rebounds and three steals in 31 minutes of action.

After scoring 17 points in the first half, Porter kept the momentum going in the third quarter with back-to-back threes that pushed Milwaukee's lead to 16 points at its largest.

Porter Jr. Is Key to Milwaukee's Success

The 25-year-old guard is absolutely essential to what the Bucks are trying to do this season, especially after Milwaukee lost Damian Lillard to a ruptured Achilles tendon last year.

Porter signed a two-year, $11 million deal to return to the Bucks this past summer and was expected to step into the starting point guard role, but injuries have made that difficult so far.

Porter missed 19 games after suffering a sprained ankle against Washington in the season opener on October 22. Then, while training to come back from that injury, he tore the meniscus in his right knee and had surgery on November 3.

Monday's contest was just his third game of the season, and the second since his return from knee surgery following a 13-point, six-assist performance against the Brooklyn Nets on Saturday.

When healthy, Porter gives the Bucks a dynamic playmaker who can create his own shot and set up teammates, which pairs well alongside Giannis Antetokounmpo, who is averaging 30.6 points, 10.7 rebounds and 6.4 assists this season.

Milwaukee (9-13) will need Porter back and healthy soon as they look to climb out of their early-season hole.

They host the Detroit Pistons on Wednesday night, and if Porter's assessment is correct, he should be ready to go.