Vertonghen struggled to hide his disappointment after the 1-0 defeat as Ben Watson's goal in the 56th minute secured the points for the visitors.
"The team is strong enough to come back from this defeat," Vertonghen told the Spurs website.
"We have a lot of important games ahead, important games in Europe and difficult away games. We have to stick together. We know we're strong in away games and we can win at any away ground."
As for the Wigan defeat, he added: "We had problems with their system, but normally we turn it around.