Containing Colombia's potent attacking game, even without injured striker Radamel Falcao, will be key to defensive-minded Greece's attempt to upset the World Cup Group C favourites on Saturday.
The Greeks, who also play Japan and Ivory Coast in the group, have long said their first game will be the most crucial one with Colombia, who finished second in the South American qualifiers after a superb campaign, seen as the team to beat.
"We have it in our own hands to beat them," said Greece's versatile defender Giorgos Tzavellas. "Colombia will have to find a way to score against us and that will be very difficult and I hopeful we will win this game. This first game is extremely important."
Greece, who 10 years ago staged a major upset by becoming European champions, have forged a reputation as a hard-working defensive team, conceding just four goals in their 10 qualifiers.
"They have a high quality attack but everyone of us is experienced. We will only play to win," said Greece defender Kostas Manolas. "We are a good team and we will prove it on Saturday."
Greece will need to be at their well-organised best with Colombia, despite the absence of talismanic striker Falcao for the tournament, having outstanding attacking options with Jackson Martinez or Carlos Bacca and a constantly changing system.
For 64-year-old Colombia coach Jose Pekerman any result other than victory would be a disappointment and he will be banking on his European mercenaries to deliver, with 15 of his 23 players plying their trade across the Atlantic.
"Colombia cannot simply change its playing style," captain Mario Yepes told reporters. "Throughout the qualifiers we relied on possession of the ball and that is what makes us strong."
That possession game includes attacking full-backs and the ability to launch rapid counter-attacks.
"Sometimes, in some games, it is normal that it does not work, but we will try to do it, " said the defender nicknamed 'Super Mario', who plays for Italy's Atalanta.
Yepes said Colombia would miss Falcao, injured defenders Aldo Ramirez and Luis Perea, along with midfielder Edwin Valencia, but their style would be the same whoever was on the pitch on Saturday.
"The idea is that Colombia plays the same way even though the names may change. We want to have the ball to play our flowing game."