DETROIT — Whether it was a showcase or the Knicks needing an extra player, interim head coach Mike Miller gave veteran shooting guard Wayne Ellington a big chance Thursday against Orlando to show he can still help a playoff team.

Ellington obliged with 12 points on 4-of-7 shooting (4-of-6 from 3), as the Knicks won, 105-103.

With the NBA trade deadline passed, it’s buyout season for players such as Ellington, who is on an expiring contract and has had little chance with the Knicks shooting-guard glut, especially since Miller took over and Reggie Bullock returned.

Ellington indeed is talking with his agent, Mark Bartlestein about his future and it is unlikely the Knicks stand in Ellington’s way.

“There will be a decision to make,’’ Ellington said at Saturday’s morning shootaround at a suburban Detroit high school before the Knicks faced the Pistons. “I’m just listening to my agent at this point. I come in here, come into work every single day like it’s a normal day. Listen and get advice and take it from there.’’

Ellington, who wanted to re-sign with the Pistons last season after helping Detroit get into the playoffs, is a 3-point shooting specialist but his shot was off earlier this season (32.6 percent), leading him to lose his spot in the Knicks rotation.

He has appeared in 25 games but probably can provide depth for a team such as the Lakers, who were shut out at the trade deadline. Ellington played for the Lakers in 2014-15.

“There’s a lot of stuff out there,’’ Ellington said. “There’s a lot of different things floating around for options. It’s part of the business. It’s part of the game. There’s nothing imminent right now. There’s nothing for sure. I’m going to keep pushing forward. We won three games in a row, try to keep that going.’’

Waiving Ellington would open up more playing time for Damyean Dotson, who also is a free agent. Power forward Bobby Portis, who is repped by Bartlestein, also could be a buyout candidate.

In Thursday’s deal with the Clippers, the Knicks didn’t want to take on rookies Terance Mann and Mfiondu Kabengele in exchange for Marcus Morris because they didn’t want to immediately waive players. That indicates the Knicks either wanted to keep the veterans for leadership or save money in a buyout scenario.

“Wayne has been — he’s the first one in the gym, the last one getting extra shots,’’ Miller said. “He’s staying ready. He does extra conditioning. He’s the ultimate pro. He’s talking to the young guys. He’s done everything you can ask a guy to do. It was great to see him getting some time and impacting the game.’’

According to an NBA source, Ellington had some value at the trade deadline but apparently not enough to make a deal. The point is, there are some playoff teams that could use the 30-year-old former UNC star.

Ellington was on pins and needles Thursday at 3 p.m.

“Of course,’’ Ellington said. “I think everybody was. It always gets crazy around this time of year, especially around the deadline. I was watching for sure.’’

When Ellington signed a deal that pays him $8 million this season, he thought the Knicks would compete for the playoffs. Even when they sputtered early on, Ellington issued a rallying cry in late November, saying they can be like the Miami team of 2016-17 that started 11-30 and finished 30-11.

Things didn’t happen that way, but at least the Knicks (16-36) were 5-5 in their past 10 entering the Motown meeting. Ellington has played a meager role in that span — even as starting shooting guard RJ Barrett went down with an ankle sprain.

“It’s part of being a professional,’’ Ellington said. “I don’t want to say it’s hard for me. That’s one of the things that keeps me focused, staying with it, is getting that work in. Not playing, you’ve got to do some extra things. Preach to guys, especially to the young guys when they’re not playing or things aren’t going their way. Get in the gym. Lose yourself in the gym. Lose yourself in your work.’’

According to Miller, Ellington went to a gym Friday night to shoot after the club arrived in Detroit. He’s staying sharp — whether he will aid the Knicks or another club in the future.

“It felt great to be able to get out there with the guys and contribute, especially to a W,’’ Ellington said of the Orlando win. “To see a couple shots go in, get into a nice little rhythm. It felt great.”