Werner has been dropped for Christian Pulisic.
Tuchel said, "On form and on work rate. We used Timo Werner lots and are close to overuse. Christian is in good form and I want to have that competition for position. We didn't do many changes in formation but Christian can show up and challenge for Timo. It is still offensive formation.
"We reacted well [in Europe] but we got under pressure with our home defeat to West Brom. We need to restart in the league. We don't start to give the impression we rest players for Tuesday because that is not the case.
"It is an important game today because it is the only game today. We have to win."