The Reds slipped to their fifth successive home defeat on Thursday night as Thomas Tuchel’s side clinched a 1-0 win thanks to Mason Mount’s superb first-half goal.
Klopp replaced Salah with Alex Oxlade-Chamberlain with 30 minutes remaining and Liverpool’s top goal-scorer did not look particularly impressed with the decision.
Former Liverpool winger Pennant was also ‘disappointed’ by Klopp’s ‘silly’ move and says it was a mistake to take off a player who can produce ‘magic’.
He told Stadium Astro: ‘I’m concerned that you’re bringing him off. You don’t bring off a player of that stature.
‘Not because he’s bigger than the club, but because what he can do on the pitch. He can produce magic, we’ve seen that every season that he’s played for Liverpool.
‘He can be quiet for 80 minutes and bring out one piece of magic when they need it. In a game like this, you should always have Salah on the pitch.
‘Bringing on Jota, great substitution. If they would have had Firmino, Jota, Mane and Salah on the pitch, they would have put Chelsea on the back foot even more.
‘Taking him off, I was baffled. You should always keep Salah on the pitch. You can’t bite your nose to spite your face.
‘Taking him off was silly. If he was on the pitch, who knows what would have happened? I think Klopp needs to be more reasonable than that, I think it was a silly decision.’
Liverpool’s defeat leaves the club seventh in the Premier League table – four points outside the top-four with nine matches of the 2020-21 campaign remaining.
Speaking after the loss to Chelsea, Reds boss Klopp said: ‘You saw the game – it was a tight one, it was a close one, it was an intense one.
‘We forced them to make mistakes, they forced us to make mistakes. They used one, we didn’t use ours. Against Chelsea, it would be surprising to play them off the pitch – but we were in the game.
‘It is just annoying to talk about the same things again and again. It is tough. We have to fight through this.’