The 29-year-old will miss games against Newcastle United, Fulham, Tottenham Hotspur and Birmingham City as well as the FA Cup third-round tie against Queens Park Rangers and the first leg of Chelsea's Carling Cup semi-final against Everton, with the club hopeful he may be fit to return for the second leg on January 23. "Scans have revealed a tear in Frank Lampard's right thigh," confirmed a club spokesman. "The tear is not in the same leg that Frank injured earlier this season. He will begin his rehabilitation immediately and we hope to have him back playing within a few weeks."

While the loss of a key player in Lampard would represent enough of a blow, it has merely compounded Chelsea's problems. John Terry is still absent after breaking three bones in his foot during the defeat at Arsenal earlier this month, Florent Malouda has a knee complaint, while Didier Drogba has yet to return from knee surgery and, should he prove his fitness, will miss up to four weeks in the new year with the Ivory Coast at the African Cup of Nations.

The tournament in Ghana will also prompt the departures of Michael Essien, Salomon Kalou and Mikel John Obi. Ricardo Carvalho, meanwhile, will miss the club's next three games after his dismissal against Villa for a two-footed lunge on Gabriel Agbonlahor. Chelsea have appealed to the Football Association against Ashley Cole's last-minute dismissal for handball on the goalline - the England full-back will learn today whether that appeal has been successful - but he, too, is currently due to sit out tomorrow's game against Newcastle at Stamford Bridge.

That has left Grant to consider how best to prioritise additions to his squad when the window opens on January 1. The new manager was always likely to be busy during the month of trading as he begins to shape a team he inherited from Jose Mourinho into his own. Interest is retained in Bolton's Nicolas Anelka, with a potential move for Modric also now more enticing to bolster numbers in midfield. "I was hoping to use the transfer window, but now, because of the suspensions and injuries, as well as the African Cup, I must think about using it more," said Grant.

The Croat, so impressive in the 3-2 defeat of England at Wembley last month, has long been on Chelsea's radar. It had been expected that Modric would move at the end of the season - Lampard, after all, has suspended talks over a new contract until the summer prompting uncertainty over his long-term future at the club.

The Dinamo Zagreb vice-president Zdravko Mamic, who also acts as Modric's personal manager, returned to London on Boxing Day and intends to hold talks with numerous Premier League clubs over his player's future over the next few days. Arsenal, Manchester City and Tottenham would compete in that pursuit, though Chelsea remain favourites to secure the 22-year-old for all that they would be reluctant to match Dinamo's £20m valuation.