Rooney was one of six Manchester United stars representing their
countries in South Africa.
They are not due back in training until July 28 and Fergie is
not ready to rush them all into the season opener against Newcastle
on August 16.
Ferguson is in Chicago at the start of United's tour of the
Americas.
He said: "Winning is part of what we have to do here - but the
main object is to get everyone game time and come back ready, fit
to start the season.
"Even the Community Shield does not come into it in terms of a
need-to-win game. It's the final part of our preparation.
"It's on August 8 and then they have internationals that week,
and then we have our first game the following Monday against
Newcastle.
"By that time, after we've surveyed the fitness of the ones
who've been in the World Cup because they don't come back until
July 28, we'll know whether any or all should play in the opening
game.
"I have a feeling we'll probably not play them all."
Ferguson will keep an eye on Rooney in particular after his
troubled World Cup.
He went into it with high expectations despite injury wrecking
the end of his season. But he failed to score or have one good game
as England flopped to a second-round exit.
Ferguson is aware of possible burn-out with his younger stars
but finds it more difficult to give Rooney, 24, a rest as the
club's top scorer from last season is always so desperate to
play.
Rooney hit 34 goals and scooped the PFA and Football Writers'
Player of the Year awards.
But on the field he ended with only the Carling Cup.Another
player Ferguson will have to assess closely when he returns from
tour is France's Patrice Evra who was at the centre of a players'
strike.
The French refused to train one day after Nicolas Anelka was
sent home for swearing at coach Raymond Domenech and there were
calls for Evra to be stripped of the captaincy and suspended.
Ji-Sung Park of South Korea, Serbian Nemanja Vidic and new boy
Javier Hernandez, of Mexico, also represented United at the finals
though one player who will not need assessing is England's Michael
Carrick who did not play. Fergie also has injury problems which
could deprive him of five more first-team players for the big
kick-off. Gary Neville (calf), Rio Ferdinand (knee) and Michael
Owen (hamstring), are doubtful while Owen Hargreaves and Anderson
are definitely out with knee problems.
But two players raring to go are new signings Hernandez and
Chris Smalling.
Hernandez, 22, was a star for the Mexicans while Smalling, 20,
is a relatively unknown defensive signing from Fulham.
United midfielder Darren Fletcher, 26, is excited by the two new
arrivals. He said: "Chris has been training and he's a big, strong,
tall lad. I think he's got great potential for the future. He's
going to be some athlete and when he learns what Manchester United
is about he'll be a top player."
Hernandez starred as Mexico made it to the last 16. He will join
at the end of the tour at Guadalajara where United play his former
club Chivas.
Fletcher added: "He's young, sharp and looks really hungry. He
scored a couple of great goals at the World Cup and I think he'll
be a good addition."
Another young arrival could be Inter Milan's Mario Balotelli,
19. United have made a £28million offer for the striker and hope to
have him by the weekend.
Midfielder Fletcher will be a senior player on tour and is
determined the trip forms a foundation for United's bid to regain
the league title from Chelsea.
He said: "It runs through your head all summer. Losing out in
the Premier League and the Champions League, you think about what
you could have done better.
"You have to try and switch off, and I managed to do that at
times but you've got to be always thinking about how you can
improve yourself."
United will play Celtic, Philadelphia Union, Kansas City Wizards
and the MLS All-Stars. The tour ends with the trip to
Guadalajara.