Carmelo Anthony once believed the Knicks had enough veteran talent to contend in the East. He started alongside three rookies Thursday night for the second straight game, and two of them were undrafted.

Anthony couldn’t have expected this. Few could have. But everything that could go wrong for the Knicks has, and now Jeff Hornacek is forced to use these kinds of lineups. It’s possible he could start five rookies in the Knicks’ season finale Wednesday. He also could start five undrafted rookies.

The roster that team president Phil Jackson put together has been just one of the reasons the Knicks will miss the playoffs for the fourth straight year and are one defeat from losing at least 50 games for the third straight year. Loss No. 49 came after Anthony missed a potential game-tying three-pointer with 2.9 seconds left and the Knicks fell 106-103 to the Wizards at the Garden.

The Knicks (30-49) have three games left, and may be without Kristaps Porzingis for all of them. Porzingis tried to play, but back spasms during a pregame workout kept him out for the second straight game.

“We do have to be careful,” Hornacek said. “It’s the end of the season. We’re not going to get in the playoffs. So we’ll keep a good eye on it.”

The Knicks erased a 15-point deficit and 12-point hole to tie the score late, but they never took the lead. Anthony scored 23 points and Justin Holiday had 16.

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Marshall Plumlee made his first NBA start, two nights after Maurice Ndour was given his first. Ron Baker also started in the backcourt. But Hornacek played four veterans and rookie Willie Hernangomez in crunch time.

Anthony made back-to-back jumpers to tie it at 101 with 1:10 to go. Bradley Beal then drilled a baseline three-pointer to put Washington up 104-101 with 49.9 seconds left. Two Anthony foul shots with 32.3 seconds left brought the Knicks within one.

Beal made it a three-point game again after hitting two foul shots with 8.9 seconds remaining. Holiday fouled Beal inside with seven-tenths of a second left on the shot clock.

Beal had 25 points and John Wall 24 for the Wizards (48-31).

Thursday night, the Knicks were without five of their projected top seven players coming into the season: Porzingis (back), Derrick Rose (knee surgery), Joakim Noah (league suspension) and Lance Thomas (hip). Brandon Jennings plays for the Wizards.

The Knicks waived Jennings in February, and he signed with the Wizards. He came off the bench Thursday night and had four points and three assists in 20 minutes. Jennings said the trade rumors involving Anthony and his relationship with Jackson “took a toll” on the team.

“This is Melo’s team, he’s a star,” Jennings said. “He had a lot of pressure on him dealing with stuff with Phil. The trade rumors, stuff like that. I think it was just a roller coaster, an emotional roller coaster for him this year with everything he had to deal with, which isn’t fair.

“That was one of the wildest situations I’ve ever seen . . . It wasn’t even about basketball anymore, it more about what was going on with Melo.”

Jackson has taken much of the blame for the Knicks’ shortcomings this season, and the past two. Former Bulls great Scottie Pippen said Jackson shouldn’t be back as president. But he’s also had his supporters, including Shaquille O’Neal and now Dennis Rodman. The NBA’s former bad boy told cbssports.com that today’s players can’t handle Jackson “mentally” and said Anthony would never win with the Knicks.

Rodman may be right. Anthony’s time with the Knicks might be nearing an end.