The Chelsea midfielder has suffered a recurrence of a calf injury, ruling him out of matches against Manchester United and Shakhtar Donetsk but Marko Marin may get a look-in
Di Matteo was facing the press ahead of Sunday's encounter with Manchester United, and conceded that Lampard will miss the game at Stamford Bridge.
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The England midfielder aggravated the pre-existing injury in Tuesday's 2-1 Champions League defeat to Shakhtar Donetsk and will miss the return leg, in addition to the United clash.
Di Matteo told reporters: "He is going to be out for a few weeks. He's got a calf problem, so we will miss him and it's a big loss for us.
"Apart from him everybody else is fit. Marko Marin might be in the squad for Sunday."
The 34-year-old had already been forced to sit out England's World Cup Qualifiers against San Marino and Poland in a bid to recover quickly from the injury, but only lasted 15 minutes against Shakhtar in the Ukraine before being withdrawn.
Lampard has played in seven Premier League matches this season, scoring three goals so far.