Oct 14 - Manchester United defender Lisandro Martinez has defended his criticism of the club's leadership following Tuesday's 2-0 Champions League defeat at Atletico Madrid, saying his comments reflected his desire to see the team compete for major honours.

The Argentina international acknowledged that frustration had shaped his post-match remarks, in which he called for greater investment in the squad and questioned director of football Jason Wilcox's recruitment efforts, but stopped short of apologising.

"After the match, I spoke out of anger and frustration at not getting the result we all wanted," Martinez wrote on Instagram on Wednesday.

"Those who know me know how I live football, with passion, commitment and a huge desire to win. And when things don’t go our way, it hurts, especially when representing a club with the history and stature of Manchester United.

"My words reflect how I feel and how much I want to see this club competing for the biggest honours."

Martinez reiterated that the players also had to take responsibility for improving the team's performances.

"I know that, first and foremost, it's us, the players, who have to deliver, and I put myself at the front of that responsibility," he said. "We need to demand even more of ourselves and work together to take Manchester United back to the top."

The defeat extended United's winless run to five matches in all competitions, adding to the scrutiny surrounding head coach Michael Carrick as the club adjusts to life back in the Champions League after two seasons away.

"I believe in my teammates, our manager and everyone working to help this club move forward," Martinez added. "I'm convinced that the way forward is to keep working together, with ambition and commitment."

Reuters has contacted the club for comment. United have not publicly responded to Martinez's remarks, although ESPN and Sky Sports reported that Wilcox retained the backing of the club's leadership. REUTERS