TONY HIBBERT and Leon Osman have handed Everton a pre-derby boost by agreeing new contracts - but David Moyes is fuming at the news Marouane Fellaini faces up to six weeks out with a hamstring injury.

Long-serving homegrown duo Hibbert and Osman will put pen to paper on new deals that are poised to extend their Goodison commitment until 2013.

And the pair are likely to be in the starting line-up for tomorrow’s Goodison derby against fellow strugglers Liverpool as Moyes grapples with more injury concerns.

With Steven Pienaar not yet recovered from a groin problem, Everton's midfield woes have been compounded by Fellaini being sidelined out for at least a month after suffering hamstring damage while on international duty with Belgium on Tuesday.

Moyes was in the crowd to watch Fellaini score in the remarkable 4-4 Euro 2012 qualifying draw with Austria before sustaining the injury.

However, the 22-year-old was asked to play on until his eventual substitution nine minutes from time, a situation Moyes is convinced exacerbated the injury and has prompted him to write an angry letter to the Belgian FA.

"Felli got injured and he continued playing," said the Goodison manager. "I thought he should probably have come off as soon as he felt it, and he’s probably made it worse.

"I will write a letter of disappointment to the Belgium FA."

Moyes had already seen Phil Jagielka pick up a hamstring problem while on England duty. The centre-back is unlikely to be available tomorrow but will not be sidelined for the four-to-six weeks Everton initially feared on his return to Finch Farm last weekend.

And while Louis Saha is also still missing as he nears a return from a calf problem, Moyes is determined to improve on a record that has seen Everton lose eight of the last 10 Goodison league derbies.

"I go into the game knowing we have a good team good players, although obviously we’re missing a host of players," he said. "Liverpool have some fantastic individual players who can win games at any moment.