The Ibrox gaffer was naturally down at being beaten 1-0 at a sweltering BayArena this evening, and 4-1 on aggregate, but was able to reflect on what has been an incredible run for the Light Blues.
He told Rangers Media at the BayArena: "We are disappointed to lose the game tonight, of course we are. You still get the same feeling of disappointment and hurt of course, but you are right, it has been an amazing journey.
"But there is still a lot we can learn from tonight - a lot of things we can improve on and moving forward, we need to make sure we continue to improve individually and collectively."
"They [Leverkusen] are top quality with fantastic players. They play with experience and at this level, they have certainly got more experience than us.
"But at times, we had pockets in the game where we did okay. We had one cleared off the line but all-in-all, we haven't done enough to certainly go through.
"But I am still disappointed we have lost the game - I wanted us to be a bit braver in possession, create a little bit more and really show that we belong at this level.
"But we were beaten over the two legs by a better team - I think there was a lot of damage done at Ibrox, and again tonight, we haven't managed to keep a clean sheet and that needs to be our base to build on."
On the journey to the Last 16 which began over a year ago in Gibraltar, the manager continued: "We will look back with immense pride. We have done ever so well and I think we have done the fans proud if you look at the whole journey.
"Tonight, maybe not so, but there is no point looking back. We need to really respect this level and individually and collectively keep trying to strive for better.
Two positives from tonight were Fil Helander making his first competitive appearance since December, and Nathan Patterson earning a European debut.
He explained on Patterson: "There was a stage in the game towards the end when I knew it was impossible to get through, so it was about offloading people for the weekend and also giving the kid an experience because hopefully, one day, he is going to be playing and competing at this level for many years.
"One positive I take from tonight was the two centre-backs - I thought Fil got a load of amazing blocks in and really kept us at bay at times.
"I thought Connor played like a European player tonight - I thought he was outstanding."
The manager also cast an eye ahead to Sunday's Ibrox match with St Mirren, adding: "It was very warm tonight and I am sure it will take its toll, but we are fit and I don't think fitness was a problem tonight and we will get the right recovery and the right information into the players and we will try to freshen it up in a few places and we will be ready to go at the weekend."