Barca's 4-0 away win at APOEL was marked by Lionel Messi's historic hat-trick - the Argentine claiming the outright most goals tally (74) from Raul (71).
The Cyprus-based club will next travel to the Netherlands for a winner-takes-all battle with Ajax on the final UEFA Champions League group-stage matchday in December - with the victor to finish in third in Group E.
More so, a draw would be enough to send Ajax through to the final stages of the European second-tier tournament - leaving APOEL with work to do before the December 10 fixture.
Donis said while he knew the troubles his side have faced on the road - APOEL have not won away in 11 European fixtures - he said his side will continue to compete for third spot.
"Despite our efforts and performance, we knew we were up against a team on another level," Donis told UEFA.com.
"The result is normal given how they played and how the game went. My players gained some valuable experience.
"It is one thing to watch them on television and something else entirely to play against them."
On their group finale, Donis added: "We know we have a hard game away to Ajax but we need to believe we can do the job there.
"But we are the outsiders and we have to accept that. I believe the players have already done what was required of them - get into the group stages and give their all in these games regardless of the results.
"It is so difficult to win away in this competition. When it is time to go there, we will go there with total faith in our abilities and fight right until the end."
Forward Rafik Djebbour said APOEL were outclassed at Barca's attacking end, as the likes of Messi and Luis Suarez ran riot.
"APOEL have a good defence, but against Neymar, Messi, Suárez, Pedro and all the attacking players that Barcelona can field, it is very hard to cope," Djebbour said.
"We will look to take our chances [for a UEFA Europa League spot].
"We still have this card to play and we can play a good match there.
"We will give everything for a victory that will enable us to continue in European competition."
