The Sweden international goalkeeper was a deadline day signing but only arrived in the UK on Thursday after playing for his country in the Word Cup qualifiers.
Following that, Olsen was forced to undergo a period of quarantine which ruled him out of Saturday’s match against Peterborough and he finally made his first appearance in a United shirt in the 2-2 draw with Preston.
However, it wasn’t the best start to life in Sheffield, with his error gifting North End the first of two equalisers as the keeper found himself wildly out to position after a long ball from the back and Daniel Johnson slotted in easily.
The 31-year-old also looked a little uncomfortable with the ball at his feet at times, when United attempted to play out.
Olsen would later atone for that by making an excellent stop to deny Emil Riis, wo would eventually go on to earn Preston a point in the final seconds of the game.
Jokanovic recognised that it wasn’t a perfect debut for the stopper but insists Blades fans will see better displays in time.
The manager said: “He's a new guy in the squad, twice we have worked with him. He needs to adapt and we need to adapt to him. We will start to work seriously in the days ahead. He made one really important save for us.
"We expect in the future he will be more comfortable and more than he did tonight.”