The Germany international wants his team to shake off recent inconsistencies and make one last push for a place in Europe by taking three wins from their last three games of the season.
"The stakes are very high," Jansen said on his club's website.
"When you have a home game and you have the chance to qualify for the Europa League, then you must not waste it.
"We have got to see this chance. If anybody had told us at the start of the season we would still be in the running for the Europa League, we would have signed for it."
They were close to going one better a week ago when a win over Schalke would have taken them up to fourth in the table.
But, like so often over the past 18 months, when they were so close to such success they collapsed, losing 4-1.
"If we can just get rid of the lapses in concentration, then we can beat anybody," said Jansen.
"This season has been a crazy one. There have been extreme ups and downs.
"But it is like a cup final. A lot can be decided."
The stakes are not so high for Wolfsburg who, with five points to make up on the top six over the remaining three games, are unlikely to find a way into Europe next season.
That does not mean they have nothing to play for, though, according to their coach Dieter Hecking.
"The players really have their foot down at present and we want that to continue in our remaining games," he said.
"We want to be the spoilsports and we are happy with this role."
Thomas Kahlenberg is unavailable for Hecking, but Simon Kjaer is about to return to the squad after recovering from a groin injury.
Hamburg's regular goalkeeper Rene Adler is suspended so Jaroslav Drobny will be between the posts for the hosts.