United were heavily linked with the RB Leipzig defender during this past summer.
The two clubs will meet at Old Trafford in the Champions League group stages on Wednesday.
"There's always rumours and speculation about good players for Manchester United," Solskjaer told reporters during at a press conference.
"I've always tried to respect [that] they are players for other teams and don't want to comment on every player we are linked to.
"But since he's playing against us tomorrow, I know he's a very good player and we can see him close up tomorrow."
On facing Leipzig, the Norwegian added: "They are a club that has come up through the ranks very impressively and almost improved every season.
"Last season, third in the Bundesliga, they've started really well, got to the semi-finals and are really going for the big trophies.
"You have a young, proactive, interesting coach to watch who's very adaptable and with players who've got high energy, high tempo - all in all, they've been very interesting to follow the last few years."