Defeat - 4-2 on aggregate - meant Porto became the first Champions League holders to fail to make the quarter-finals.

Adriano appeared to have put Inter in total control with a deflected shot and a cool finish giving the hosts a two-goal lead, but a scrambled effort from Porto's veteran defender Jorge Costa ensured a nail-biting climax.

However, Adriano had the final word, settling Inter's jangling nerves four minutes from time with a superb solo effort.

By joining Serie A rivals Juventus and AC Milan in the last eight, Inter have kept their season alive as they trail joint league leaders AC Milan and Juve by 16 points and with 10 games left they have practically no chance of closing the gap.

Victory against Porto maintained Inter's unbeaten home record against Portuguese clubs in Europe with seven wins and a draw.

Inter coach Roberto Mancini was delighted to see Adriano return to his brilliant best, having scored just one goal since December 12 before facing the reigning European champions.

"I'm very pleased for him and he deserves it," Mancini said.

"All strikers go through a difficult period and he's no different - all that was needed was a bit of calm. He didn't go on holiday, he just stuck at it and now he's reaping the rewards."

Inter, winners of the old European Cup in 1964 and 1965, were handed the perfect start in the sixth minute when a misplaced pass by Porto Diego went straight to the predatory Adriano.

The burly Brazil international burst into the box before drilling an angled shot that deflected heavily off Pedro Emanuel and looped over Victor Baia and into the net.

Adriano then doubled his tally in the 63rd minute, springing the offside trap to collect Cruz's pass before stabbing the ball past Baia with his trusty left boot.

Veteran George Costa hauled Porto back into the match, prodding home from a yard out after Toldo had failed to collect a corner.

Pedro Emanuel's goalline clearance prevented Javier Zanetti from restoring Inter's two-goal cushion before Adriano carved his way into the box and beat Baia with a left-footed curler.