Salah joined the Reds from AS Roma in a £36.9 million deal last month, but was unable to feature in Wednesday night’s pre-season opener at Tranmere Rovers due to work permit issues.
However, the Egypt winger returned from a trip to Paris to take his place in Klopp’s starting lineup at the DW Stadium.
And Salah produced an encouraging display, including the first shot on goal after just two minutes.
After Alex Gilbey had opened the scoring for the Latics, Salah equalised on the stroke of half-time, capping a positive 45-minute performance that Klopp feels still needs improvement.
“You saw he had no idea how we defend usually, so he was really not involved in this,” he told reporters after the game.
“He had two days with us, then he had to go to Paris, get the papers, but now he’s here and we thought ‘let’s play him’.
“He’s really used to a completely different way of defending, but the first situation, nice sprint.
“And the goal was maybe the easiest situation in the game, but they played a few wonderful pieces of football: Roberto, Phil, Adam, Gini in the No. 6 position was good.
“So it was OK, just not where they can be. It’s just a sign, but that’s important.”
While it would be remiss to gauge Salah’s influence on one half of a pre-season friendly away to League One opposition, his impact was clear.
The pace that he brings to Klopp’s attacking line is invaluable, and while he was out of sync with the Reds’ pressing game, he remained a diligent defensive presence in the final third.
In many ways, his first outing for the Reds mirrored that of Sadio Mane away to Tranmere last summer, and Klopp will hope he can adjust quickly like the Senegalese.
It is unlikely Salah’s full potential will be showcased until the campaign starts proper away to Watford on August 12, however, with these pre-season cameos very much “just a sign” of things to come.