Oscar's first Premier League goal of 2013 has given Chelsea a narrow half-time advantage over Liverpool at Anfield.
The Brazilian international planted a powerful near-post header beyond Pepe Reina on 26 minutes after breaking free of marker Jamie Carragher at a corner kick.
Liverpool had been in the ascendancy prior to the goal and the Reds squandered a great chance to break the deadlock in the opening five minutes of the game.
Glenn Johnson played a neat one-two with Luis Suarez, but the England full-back could only poke his effort just wide of Petr Cech's goal.
Chelsea grew in confidence after going ahead and almost doubled their lead on the half-hour mark, as Reina fumbled a David Luiz free kick that came very close to bobbling over the line.
Suarez has scored seven goals in his last eight appearances and the Uruguayan had a chance to continue that fine run late in the half.
However, Cech made a fine block to ensure that the Blues returned to the dressing rooms in front.