Arsenal and United used to fight each other for titles, but advantage in the race for third place is on the line when the two teams lock horns at Old Trafford on Sunday.
Although Arsenal have a match in hand, defeat at Old Trafford would mean they drop to fourth place, one point behind United.
Having finished in fourth for six of the last nine seasons, Wenger knows all about the accompanying Champions League play-off ticket.
Van Gaal knows how hard it can be to qualify for the Champions League through the preliminary stages too having squeezed past Skonto Riga with Barcelona in 1997 and he is keen to avoid another difficult playoff.
"We can say we have qualified for the Champions League, but that is not true," the United manager told MUTV.
"Maybe Liverpool cannot chase us anymore but we have to play a game before the entrance into the Champions League and that game is always tricky
It is not easy
There are not existing any easy games any more.
"We can give pressure to Arsenal and that is what we want to do on Sunday."
Van Gaal watched on with angst as his star-studded Barca team struggled past their Latvian opponents 18 years ago.
Despite the presence of the likes of Luis Enrique, Pep Guardiola and Luis Figo, Barca went 1-0 down to Skonto at the Nou Camp and needed a last minute winner from Hristo Stoichkov to edge the first leg 3-2 before taking the return fixture 1-0.
Much bigger fish lie in wait for United next year
Although they would be seeded, Van Gaal's team could face the likes of Monaco or Lazio in the playoff, which would take place in the final two weeks of August.
Still, Van Gaal would have taken fourth place at the start of the season or at the beginning of November after United had won just three of their opening 10 league games.
The Dutchman is proud of his achievements, particularly when he considers how many changes he has had to make since he took charge last July.
"It was a big challenge because when I came here, a lot of players were here," he said.
"I let a lot of players go
We have let go more than 15 players go and we bought only five players and we did it with a different team as the year before.
"We want to be the champion
Now at the end we want to be third because it is still possible."
Van Gaal is happy to have achieved his aim of turning Old Trafford into more of a fortress again.
Under David Moyes, United lost seven times at home in the league, but since their opening-day defeat to Swansea, Van Gaal's team have only lost twice at Old Trafford - to West Brom and Southampton.
Only Chelsea have a better home record this season.
"I said at the beginning of the season, that we have to be so strong that everybody has the fear to come to Old Trafford," Van Gaal said.
"I think that we have succeeded in that goal."
Source : PA
Source: PA