"What happened in the Champions League final with Loris Karius, yes it was disappointing for the Liverpool supporters on the night losing that game, but we've all been there as players where you have a poor game".
In the second half at Anfield, midfielders Fabinho - who missed an early penalty - and Marko Grujic both filled in as Van Dijk only played 45 minutes, but Klopp is not anxious ahead of Sunday's visit of West Ham.
Though Liverpool face Torino in their final summer friendly at Anfield on Tuesday, the teenager is not expected to be ready for the start of the campaign after his extended break following England's run to the World Cup semi-finals.
Karius, who was the starting goalkeeper for Liverpool last season, had a poor performance at UEFA Champions League Final against Real Madrid.
He was clearly moved by this emotional gesture on the pitch and tweeted afterwards: "Thank you Anfield for this reception!".
Karius had to wait all summer for a chance to get back to playing after that match and made more headlines during pre-season with errors as he struggled for confidence.
Manager Jurgen Klopp added in quotes published on Liverpool's official website: "It helps everybody".
Jürgen Klopp was delighted to see Danny Ings back in action for Liverpool but admitted the striker's options are "open".
"Liverpool will give the title a go, they're the second best now, I think they've bought very well, very well", Merson told Sky Sports.
"He was in really good shape so we thought a few minutes tonight would be possible". Obviously he was not feeling really well so we sent him home again and I didn't see him so far and I didn't ask anybody, so we will see.
There had been wholesale changes - including Loris Karius replacing Alisson on the latter's maiden Anfield appearance - and two substitutes combined to make sure of victory.