Real Madrid midfielder Kaka says Wayne Rooney and Robin van Persie are Manchester United's chief threats ahead of their clash on Tuesday.
The Spanish champions were held to a 1-1 draw in the first leg of the Champions League round-of-16 tie at the Santiago Bernabeu, but Kaka is confident Madrid have what it takes to progress from the return fixture at Old Trafford.
"United have a traditionally European squad that always goes far in the competitions they play in. They also have some amazing individual players like Rooney and Van Persie," Kaka said.
"Manchester are really strong but we're going to Old Trafford with confidence. The stadium is fantastic, with the atmosphere and the fans.
"We came off the first leg in the Bernabeu with the feeling that we could have won the game and that we can decide the draw in England and win the playoff."
Rooney, meanwhile, says he feels as fresh as ever as the Red Devils head into a crucial period of fixtures in the Premier League and Champions League.
Rooney scored as United beat Norwich to extend their lead to 15 points at the top of the table on Saturday, with rivals Manchester City due to play on Monday night.
Ahead of the Champions League clash with Real, Rooney said his occasional injuries, coupled with his manager's rotation policy, have left him with plenty more to give.
"I haven't played as many games as I normally would have at this point in the season," Rooney said. "I feel fresh and ready for that battle until the end of the campaign.
"It's been a bit of a stop-start season for me with a couple of injuries, which has been a bit disappointing.
"I just want to keep myself fit until the end of the season now and play a part in as many games as I can to help the team be successful.
"With the way the manager rotates the team, there will be a lot of players who are feeling fresh as well.
"We know Real Madrid is a massive game but this (Norwich) was just as big. We weren't thinking about Tuesday but, now it's over and we've got the three points, we can focus on Madrid."
United conceded the title to City in dramatic style last season but Rooney believes that silverware in 2012-13 could set the tone for the current squad to achieve further success in the years to come.
"This is a brilliant squad with a fantastic mix of experienced players and young players who all have great ability and a real desire to win," he added.
"Being successful this season is really important because it would give us a great platform to kick on in the next few years.
"Once the young players have got their first taste of silverware with the club, they'll realise just how good it feels. They'll want to keep doing it again and again."