Rudiger was an unused substitute in Chelsea’s 3-1 win against Brighton last weekend and he was left out of Sunday’s 2-0 defeat to the Premier League champions at Stamford Bridge.
That decision sparked speculation over the German’s future at the club, particularly following the arrival of Thiago Silva on a free transfer from Paris Saint-Germain.
However, Lampard insists it was simply a case of ensuring he had a balanced bench and says people shouldn’t read too much into Rudiger’s absence.
‘On Rudiger, I’ve got five centre-backs at the club. I can’t pick a squad that has three of them on the bench,’ said Lampard.
‘That’s the way it is, I have to pick the squad via training and situations and the opponents and that was a selection one today.’
The Dane was sent off on the cusp of half-time after taking down Sadio Mane, who was put through on ball following a sensational pass from Jordan Henderson.
Lampard hopes to have Ben Chilwell and Thiago Silva fit in the next fortnight.