Despite being United's ?30.75million record signing and sharing last season's Premier League Golden Boot prize with Carlos Tevez, Berbatov has been a peripheral figure in the Old Trafford outfit's sensational start to the season, but he retired from international duty after Bulgaria failed to reach the 2010 World Cup.
"From a Manchester United point of view, it would have been better if he played," said Rooney. "From England's it's better if he doesn't. He hasn't had much game time at the start of the season."
He added: "But he is a massive player for us. I am sure he'll feature and be a big part of our season. He's won Bulgaria Man of the Year about seven times, so he is a big character over there."
There will be plenty of familiar faces around Rooney in Bulgaria anyway given he is one of five United representatives in the England squad.
The inclusion of new boy Ashley Young was hardly a surprise.
However, it could hardly have been imagined that Rooney would be accompanied on senior England duty quite so soon by Phil Jones, Tom Cleverley and Chris Smalling given they were part of an under-21 squad that did not exactly cover themselves in glory at the European Championships this summer.
Their early-season performances for United have demanded inclusion though, and together with the likes of Jack Wilshere, Andy Carroll and Daniel Sturridge, point to a bright future for England where 12 months ago, one did not seem to exist.
"Everyone should be excited," said Rooney. "There are a lot of young players coming into the England team, which is maybe something we haven't had before, certainly over the last 10 years.
"These lads give us a lot of different options."
Source: PA
Source: PA