Ronaldinho on the spot for Barcelona

FC Barcelona's players celebrate after scoring against Shakhtar Donetsk during their Group F Champions League football match at the Nou Camp in Barcelona

Brazilian World Cup winner Ronaldinho marked his Champions League home debut for Barcelona by scoring a second-half penalty to give the Spanish giants a 3-0 victory over a gutsy Ukrainian outfit Shakhtar Donetsk in their Champions League Group F clash.

A first half goal by Portuguese international, and Champions League winner, Deco had got them off to a good start but they had to fight hard to defy Shakhtar, who had come in to the match on the back of their eight successive wins in their domestic championship.

Cameroon international Samuel Eto'o scored his third goal in the last two matches to round it off a minute from time.

It gave Barcelona, playing in their ninth Champions League campaign, a perfect six points after two matches while Shakhtar are up against it after two successive defeats.

Barca started the second-half in lively fashion as they went for what should be a killer second goal as first Deco and the French international Ludovic Giuly had efforts saved by Jan Lastuvka.

The all-action Deco forced the Ukrainians Czech 'keeper into another save on the hour mark moments after Giuly had sent a shot wide, though they weren't having it all their own way as it required a smart tackle from Brazilian World Cup winning defender Edmilson to stop Zvonimir Vukic slipping free.

FC Barcelona's Brazilian Juliano Belletti(L) challenges Shakhtar Donetsk's Evaeeverson da Silva Brandao(R) during their Champions League football clash in Barcelona

However after both Giuly and Deco had gone close again Ronaldinho stepped up to end any doubts about the result in the 64th minute as he crashed the ball home from the penalty spot after being fouled by Lastuvka.

Belletti signalled Barcelona's attacking intent early on in the first-half when he lashed in a shot in the third minute but it went wide of the Shakhtar goal.

With Ronaldinho running the show and Belletti causing trouble down his flank the Ukrainians reverted to robust tackles fouling constantly both Brazilians.

Norwegian referee Terje Hauge eventually lost patience and put midfielder Mariusz Lewandowski's name into his book in the 11th minute.

However they were unable to stop Ronaldinho delivering the killer ball to Deco in the 15th minute, as he struck firmly home past Lastuvka to confirm their early dominance.

Shakthar almost broke their duck in scoring in Spain - having failed to find the net on two previous visits including a 3-0 drubbing against Barca in 1978/79 - three minutes later when skipper Anatoly Tymoschuk let rip with a stunning freekick that went just wide of Victor Valdes' post.

Shakhtar's Yugoslav playmaker Zvonimir Vukic then saw his shot on the half hour mark blocked as they began to settle down.

Their growing confidence was illustrated a minute later as their 18-year-old Romanian striker Ciprian Marica sneaked in and saw his shot saved well by Valdes.