PSG eased into the semi-finals on Tuesday thanks to a double from Angel Di Maria and a late third from Thomas Meunier.
Paredes impressed in the opening 45 minutes at the Parc des Princes as the hosts dominated, Di Maria and Julian Draxler also playing starring roles.
However he struggled to maintain that throughout the match and that is something Tuchel is keen for his new signing to improve.
"He played the first half very well, like the whole team," Tuchel told a media conference.
"In the second half, his position was a little too deep.
"He's a guy who can make very precise passes, very quickly, it's his job to set the pace and speed up the game."
Paredes was not the only one to take their foot off the gas in the second half, something that left Tuchel feeling a little tense despite PSG's control of proceedings.
"I loved our first half, our speed, our possession," he added. "The match was a bit too open for me.
"It was very intense. It must be said that Dijon played a good match. It was very impressive, they played with a lot of courage."
The French side have a 2-0 lead on their English rivals, having topped the Red Devils behind goals from Presnel Kimpembe and Kylian Mbappe.