Croatia and Spain will meet for the first time in a major tournament tonight when they go head-to-head in Gdansk.
Both on four points after two games, the teams currently sit second and first respectively in Group C.
Croatia must win if they are to top the group while, barring Italy scoring a hatful against the Republic of Ireland in Poznan, a draw should be enough for Spain.
Vicente del Bosque's men can only be eliminated if they lose and Italy win, but a low-scoring draw would put Croatia at risk.
However, and this is where it gets controversial, a high-scoring draw of 2-2 or above would guarantee that both Spain and Croatia qualify regardless of the result in Poznan.
Spanish midfielder Xavi has dismissed suggestions that both teams might deliberately manufacture a mutually favourable result and he has promised that his side will attack.
He said: "We only know how to play attacking football so a draw would not suit us.
"We will go out determined to hold possession, to move the ball and to go forward. This is our style of game and the one that made us European and world champions.
"Our aim is always to go out for victory and against Croatia it will be no exception. We will play to get three points from the first minute until the last."
Croatia's Nikica Jelavic is the only injury doubt ahead of the game. The Everton forward missed training on Saturday with a fever, but he is expected to recover in time to start for Slaven Bilic's side.
Del Bosque may decide to rest Xabi Alonso, Alvaro Arbeloa and Fernando Torres, all of whom are one yellow card away from a suspension.
Recent form:
Croatia: DLWDWD
Spain: WWWWDW
Possible starting XIs:
Croatia: Pletikosa; Srna, Corluka, Schildenfeld, Strinic; Vukojevic, Rakitic, Modric, Perisic; Mandzukic, Jelavic
Spain: Casillas; Juanfran, Ramos, Pique, Alba; Busquets, Fabregas
Silva, Xavi, Iniesta; Llorente
Sports Mole says: 1-3