Liverpool manager Rafael Benitez said striker Djibril Cisse still had more to prove despite scoring the winning goal for the second successive match in Wednesday's 1-0 victory over Anderlecht.
"He (Cisse) scored tonight, but he also missed some chances," Benitez told Reuters after a win that put the holders within sight of qualifying for the next phase of the Champions League.
"(Rival striker) Fernando Morientes is not 100 percent (fit) and we also have options with Peter Crouch and Harry Kewell. So, (Djibril) Cisse still has to keep proving himself."
Benitez was happy with the points but was less pleased with the performance in Brussels, particularly up front.
"We had a lot of chances to get the second goal, but we lacked the finish," he said.
"Anderlecht were always going to be the team under pressure and they came at us," he said. "They had chances and they could have had a penalty.
"But we knew that and approached the game that way, hoping to catch them on the counter-attack."
The Liverpool boss said his side, who like Chelsea have seven points out of a possible nine in Group G, now knew what they had to do to qualify.
"It's simple, we beat Real Betis in our next game and we are through," he said.
Anderlecht laid some of the blame for their defeat at the door of Swiss referee Massimo Busacca.
Coach Frank Vercauteren said the official "was not up to UEFA Champions League standard."
The Brussels side, whose defeat was their 10th straight loss in the Champions League, were angry after having two penalty appeals turned down in the second half.
First Jamie Carragher's arm seemed to connect with the ball from a Christian Wilhelmsson shot, while late on Wilhelmsson felt he was brought down in the penalty area.
"I am very disappointed not to have been awarded a penalty. I thought both were penalties, but the first more than the second," Vercauteren said.
Wilhelmsson echoed his coach's view, saying: "I definitely thought it was a handball. I cannot believe that he didn't give it."
