The Blues have an uphill task to stay in the competition ahead of the second leg at the Allianz Arena in three weeks’ time after being humbled at Stamford Bridge.
Serge Gnabry scored twice and Robert Lewandowski netted the other, while Chelsea also had Marcos Alonso sent off late on.
“They need to understand the levels that the Champions League is when they get to the knockout stage,” Lampard told the Metro.
“They need to use it as a positive effect. It might not feel like it this evening. A lot of players there haven’t played it, or maybe a few years ago.
“When you have an eye opener the only answer is to just look at yourself.
“I thought Kovacic played with a personality and a quality that makes you go; ‘Okay, he can play in pretty much any team with that level.’
“I learnt about the players. We went with the system that worked well at the weekend. It is how you go up about that.”
On what was a sorry night for Lampard’s side, Tammy Abraham also limped off late on with what looked to be yet another injury.
However, two players who won’t be playing in Munich is Jorginho and Marcos Alonso.
Jorginho picked up a yellow card for dissent, while Alonso was sent off late in the game following a clash with Lewandowski.
Initially he was given a yellow, but the referee then looked at the incident on the pitch side monitor and gave the left-back a red card.