The Belgians lead Group A on 22 points from eight games, five more than Croatia, and head into the clash knowing a draw would secure qualification for next year's finals in Brazil ahead of their final game at home against Wales next week.
Defender Vincent Kompany and striker Christian Benteke have been ruled out, although the latter could be fit for the Wales match, while half-fit defender Thomas Vermaelen is also doubtful after a long injury layoff.
Having completed Tuesday's training session, the towering central midfielder appears set to start against the Croatians wearing a protective cast.
"You don't get much rest these days and that can lead to injuries, but fortunately our squad is large enough to cope and we proved that (in a 2-0 away win) against Scotland (last month)," Spurs centre back Vertonghen told Belgian television.
"Friday is a chance to seal qualification and we shouldn't let it pass. We can measure up to Croatia and although we will have to be at our best to get even a draw, we are going for a win."
Wilmots, whose quality-packed side have dropped only two points in the campaign - a 1-1 home draw against Croatia a little more than a year ago - was adamant the side would adopt an attacking approach despite only needing a draw.
"If I told my players that I wanted to play defensively for a draw they would cut my head off," joked the 44-year old former international, who played for Belgium in their last World Cup appearance at the tournament in South Korea and Japan.
"Why wait if we can qualify immediately? This is our philosophy and we are not counting on a second chance against Wales because we are going to Croatia to win," he said.
Romelu Lukaku, who has been in good form for Everton since joining them on loan from Premier League rivals Chelsea earlier this season, is likely to start as a lone frontman with Kevin De Bruyne and Eden Hazard set to operate on either flank behind him.
Croatia will finish at least second no matter what they do in their last two games but June's 1-0 home defeat by Scotland left their hopes of automatic qualification hanging by a thread and seems to have dented the spirit of their passionate fans.
Coach Igor Stimac will be forced to field a makeshift defence missing suspended centre back Josip Simunic and captain Darijo Srna, with Vedran Corluka deputising as skipper.
Corluka said the atmosphere "surrounding the team" was poor but he remains optimistic that Croatia, who missed out on the 2010 tournament in South Africa, will prove their worth in the Maksimir stadium.
"The atmosphere in the dressing room is still good but it's a poor one around it because Belgium are firmly in the driving seat and that's where we wanted to be at this stage," Corluka was quoted as saying by Croatian media.
"There is no point in looking back at what might have been but I think that although the Belgians are a class act, they are not better than us. We showed that in Brussels and we will show that in Zagreb too."
Stimac added: "The Belgians are quick and skillful but they had a dip in form and unfortunately for us, their opponents did not take advantage of that."
Europe's nine group winners will qualify automatically for the 32-nation tournament in Brazil, while the eight best runners-up will enter two-legged playoffs for the continent's remaining four berths.