Gladbach will be looking to put their somewhat disappointing Bundesliga form behind them when they make the trip to Parkhead to take on the Scottish champions on Wednesday evening.
Borussia have only managed to pick up one victory in their last four league outings and have not claimed a single point in the Champions League so far this season.
Amidst the poor run, Wendt is looking forward to the trip to Glasgow and a chance to go head-to-head with Sweden team-mate Lustig.
He told the Scottish Sun: “I know Mikael well from being in the Sweden squad with him and he’s a very good friend.
“He has been at Celtic for a long time now and is a very good player, so I am looking forward to seeing him.”
Southampton have announced plans for a two-week tour of China as part of their pre-season preparations for the 2018-19 season.