David Beckham has warned Manchester United that Cristiano Ronaldo will be inspired by his return to Old Trafford for the second-leg of Real Madrid's Champions League tie with the Premier League leaders.
Beckham, 37, will watch his two former clubs clash next Wednesday before PSG look to secure their place in the quarter-finals against Valencia on Thursday.
The former England international, who made his full debut for the Parisiens on Sunday, believes Ronaldo has proved he can step up on the big stage and his former stomping ground is the perfect platform to do just that.
"It will be an exciting game, and a special night for Cristiano going back to Manchester," Beckham said. "United has a special place in his heart. The fans love him and it will be a great occasion.
"You enjoy going back [to your former club] and I am sure it will inspire him. Many things inspire great players and him going back will be a special night.
"United did very well at the Bernabeu. It will be a great game to watch. They are two great teams with great players, so it's difficult to call."
PSG take a two-goal lead into their second-leg tie, but will be without striker Zlatan Ibrahimovic who picked up a two-game Champions League suspension after being sent off in Valencia last month.
While Beckham is confident in his side's ability to keep their European hopes alive, he has urged AC Milan not to rest on their 2-0 lead over Barcelona.
"It's exciting to be back and this will be a big game for PSG," he said. "We've got ourselves in a good position by winning away but that doesn't mean it will be easy here. As long as we play well and work hard, we'll be OK.
"The competition still has the big guns and it is nice to be in it. People are talking about a shift in power with Barcelona having lost their first game [2-0 against Milan], but no one should ever doubt their players even now.
"They have a home game to come and it doesn't matter if they're two or three down... I know what it's like to play against them when they're up against it and it's not easy."