Brazil beat Croatia to become the first team to win eight successive matches in the World Cup finals.
Kaka scored his 10th goal for Brazil in the win over Croatia
Croatia's tactics frustrated Brazil for much of the match, but just before the interval Kaka's wonderful curling left-footed shot beat Stipe Pletikosa.
Pletikosa's opposite number Dida frequently came to Brazil's rescue, notably with second-half saves from Dado Prso and Ivan Klasnic.
Brazil finished strongly, with Kaka again going close with a rasping shot.
The Brazilians might be favourites to claim the "Hexa" - a sixth World Cup - but the way Croatia made Carlos Alberto Parreira's side work for this win suggests the world champions are not without their weaknesses.
Strikers Ronaldo and Adriano looked subdued throughout and it took 55 minutes for the much criticised Real Madrid striker to have a shot at goal.
The unhappy Ronaldo was eventually replaced by Robinho, whose introduction served to bring greater attacking fluidity to the Brazilian side.
But the fact that Dida was one of Brazil's best performers gives an indication of just how well Croatia played.
Prso's strong running troubled the Brazilian defence and early in the second half the Rangers striker powerfully shrugged off Lucio before testing Dida with a low shot.
Soon after making that save Dida's positioning allowed him to safely gather a Marko Babic shot.
While Prso provided an attacking outlet for Croatia, the Balkan side's defence managed to stymie Brazil for long periods.
Pletikosa, who was making his 50th appearance for Croatia, had a quiet introduction to the game, but on 15 minutes the Croatian goalkeeper came under intense pressure.
He athletically tipped a Roberto Carlos shot over the bar and then pushed away a Ronaldinho effort that came to Pletikosa through a packed penalty area.
Just after the hour Pletikosa made the best save of the game when he kept out a poweful Ronaldinho header.
Not that Croatia were ever content to solely soak up Brazil's attacks.
Prso frequently drifted out to the left and looked impressive with some strong running, while Ivan Klasnic and Niko Kranjcar had speculative shots.
Those two efforts did not trouble Dida, but seven minutes before the break the Brazilian keeper had a real scare when Igor Tudor came desperately close to reaching Darijo Srna's dangerous inswinging free-kick from the left.
Having subdued Brazil for 44 minutes, Croatia fell behind to a wonderfully constructed and taken goal.
Midfielder Emerson started the move, surging into the Croatia half before feeding the ball to Cafu.
The Brazilian right-back slipped the ball inside to Kaka, who after switching the ball quickly to his left foot, beat Pletikosa with an unstoppable shot.
It was a superb goal which hinted at the power and skill of the Brazilians.
Brazil: Dida, Cafu, Lucio, Juan, Carlos, Ze Roberto, Emerson, Ronaldinho, Kaka, Adriano, Ronaldo (Robinho 69).
Subs Not Used: Cicinho, Cris, Fred, Gilberto, Julio Cesar, Juninho, Luisao, Mineiro, Ricardinho, Rogerio, Silva.
Goals: Kaka 44.
Croatia: Pletikosa, Simunic, Robert Kovac, Tudor, Simic, Srna, Babic, Nico Kovac (Jerko Leko 40), Kranjcar, Prso, Klasnic (Olic 57).
Subs Not Used: Balaban, Bosnjak, Butina, Didulica, Ivan Leko, Modric, Seric, Tokic, Tomas, Vranjes.
Booked: Nico Kovac, Robert Kovac, Tudor.
Ref: Benito Archundia Tellez (Mexico).
Fifa man of the match: Kaka.
Brazil have won their last eight World Cup matches which is a new record, breaking Italy's seven successive victories between 1934 and 1950. Brazil's last defeat dates back to 1998 when they lost the final against France (3-0). They've kept a clean sheet in their last three World Cup matches.
Brazil have remained unbeaten in their World Cup opener for the 16th consecutive time, winning the last seven. Croatia suffered their first defeat since a 2-4 loss to England on 21 June 2004, during Euro 2004, a streak of 10 matches.
Six of Croatia's 11 World Cup matches have ended with a 1-0 scoreline (two wins, four defeats).