Manchester United defender Lisandro Martínez apologized on Thursday for publicly criticizing the club's leadership, BBC Sport and the Guardian reported.

After United's 2-0 Champions League loss at Atlético Madrid on Tuesday, Martínez said the club had left head coach Michael Carrick with an under-equipped squad and that he expected "more from our technical director," Jason Wilcox, BBC Sport reported.

Martínez posted his apology on Instagram after meeting with club leaders, the outlets said. "It was a very positive conversation, where we were able to exchange views and speak openly about what happened after Tuesday's game," he wrote. "The frustration of the defeat led me to express how I felt at a time and place that perhaps were not the right ones, and for that I want to apologise."

BBC Sport reported that the 28-year-old Argentine was fined by the club. The Guardian said it is thought he was fined. The issue is now considered closed, BBC Sport said.

"Our club is at its best when we are all united, and I recognise that my words in that moment did not help with that," Martínez said.

United are 13th in the Premier League with six points from six games, BBC Sport reported. They play Leeds at Elland Road on Sunday, with kickoff at 2 p.m. in Britain, or 9 a.m. ET, according to the league's schedule. BBC Sport said it remains to be seen whether Carrick will pick Martínez for that game.

His contract runs out next summer, and the club has yet to decide whether to use an option to extend it, BBC Sport reported. Former United captain Roy Keane, speaking on The Overlap podcast, called the situation at the club "a bit of a circus," BBC Sport reported.

What we know: Martínez apologized after meeting club leaders, and BBC Sport says he was fined.
What we don't: Whether Carrick will play him at Leeds on Sunday.