Elsewhere, Barca edged APOEL 1-0, Chelsea held 1-1 by Schalke, Ajax drew 1-1 with PSG, Maribor vs Sporting ended 1-1 and Bilabo vs Shakhtar finished goal-less.
Lionel Messi set up Barcelona's only goal in a 1-0 win over Cypriot club APOEL on Wednesday for an uninspiring Champions League debut for coach Luis Enrique.
Roberto will put pen to paper on his new deal on September 26 with a buyout clause worth â‚¬40 million.
Barcelona coach Luis Enrique has also included Brazilian back Douglas for the first time since his signing.
After a positive start, when the defensive weakness that wrecked last season appeared to have been ironed out, hopes are high Barcelona can challenge for silverware again.
Barcelona should have right back Alves back for Wednesday's Champions League Group F opener against Cypriot side APOEL.
Neymar came on as a substitute to score twice from passes by Lionel Messi and give Barcelona a 2-0 win at home over Athletic Bilbao in the Spanish league.
Barcelona say Lionel Messi has recovered from a leg injury and has been included in their squad for Saturday's Spanish league match against Athletic Bilbao.
Messi and Neymar are fit for Saturday's La Liga game at home to Athletic Bilbao, with manager Luis Enrique saying that he has an almost complete squad to choose from.
"He has been training very well these past three weeks and he does not have any problems," said Ancelotti.
Real Madrid already lost the Spanish Super Cup to Atletico, and now find themselves in 10th place in the league.