The Chelsea midfielder flew home from Doha on Thursday night amid worries he would be out until Christmas with a problem in his thigh muscle.
But Italian Capello said: 'I think he will be out for two or three weeks. It is a little problem with his muscle.'
Treatment room: Lampard (right) trained with his England team-mates earlier in the week but he was forced to withdraw from the squad to face Brazil
Capello rejected suggestions the plane on which they flew to the Middle East was to blame for the problem.
'It is the same plane (we used to fly to) Trinidad and Kazakhstan,' he said.
Lampard joined a lengthy absentee list for the friendly against Brazil, with squad regulars Rio Ferdinand, David Beckham, Steven Gerrard, Glen Johnson, Ashley Cole, Emile Heskey, Carlton Cole and David James all missing already.
Lampard was back at Chelsea's training ground on Friday morning and the club's own medical staff concurred with Capello's assessment.
'The midfielder reported back at Cobham this morning having flown back from the Middle East,' read a statement on the club's website.
'The Chelsea medical department's initial impression is that he may take approximately three weeks to recover.'
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