* Benfica must match Celtic's result against Spartak to qualify
* Barcelona have already won Group G
* Messi chases Gerd Mueller's record
LISBON, Dec 4 (Reuters) - Benfica have enough quality to get the result they need to reach the Champions League last 16 away at Barcelona on Wednesday, whether or not the already-qualified Catalans decide to rest Lionel Messi for their final group game, coach Jorge Jesus said.
The "Eagles" are second in Group G, level on seven points with Celtic, but have a better head-to-head record than the Scottish outfit. They need to achieve a result that at least matches Celtic's at home to Spartak Moscow to reach the last 16.
"Celtic may even qualify but if we don't count Barcelona, Spartak and us are the strongest of the group, in my opinion," Jesus said.
"I'm sick of repeating that Barcelona are the best in the world. Still, we go to Barcelona with a lot of confidence."
Jesus has injury concerns over midfielders Eduardo Salvio, Enzo Perez, Pablo Aimar and Carlos Martins, but said his side will travel believing they can surprise Barca in their own back yard.
"The truth is they have one player who makes the difference and, without him, Barcelona are not as strong," Jesus said. "Whether or not (Lionel) Messi plays, we go there to win."
World Player of the Year Messi created both goals in Barca's 2-0 win in Lisbon in October and may get another stab at beating former Germany and Bayern Munich striker Gerd Mueller's record of 85 goals scored in a calendar year set back in 1972.
The Argentine forward netted twice in the 5-1 rout of Athletic Bilbao in La Liga on Saturday, and is now just one goal short of Mueller's tally.
The victory also saw Vilanova's unbeaten side extend their lead at the top in Spain to six points and set a new La Liga record start to a season as they racked up their 13th victory in 14 games.
"I don't know what went wrong last year," Messi told Dutch magazine Elf Voetbal, referring to the last season of Pep Guardiola's reign when they finished second in the league behind Real Madrid and fell in the Champions League semi-finals to Chelsea.
"It serves as a reminder for something we don't want to happen again, and that we should always hunger for more in the future."
Messi has been the top scorer in the last four Champions League seasons and has netted five times in the current campaign.
"We are going to have to run and suffer because we know they usually have 60 or 70 percent of possession so we will need to take the few chances that come our way," Benfica forward and Spain under-21 international Rodrigo said in an interview with A Bola sports daily.
"Everyone talks about Messi but if he is not in the squad, it's (Andres) Iniesta, (Cesc) Fabregas, Xavi or Pedro. It will be very tough. We played a good match back at home against them. We lost but it was not as unbalanced as many expected."
Barcelona: 1-Victor Valdes; 21-Adriano, 3-Gerard Pique, 14-Javier Mascherano, 18-Jordi Alba; 25-Alex Song, 11-Thiago Alcantara, 8-Andres Iniesta; 17-Pedro, 10-Lionel Messi, 7-David Villa.
Benfica: 1-Artur; 34-Andre Almeida, 4-Luisao, 24-Ezequiel Garay, 25-Melgarejo; 15-Ola John, 21-Nemanja Matic, 11-Lima; 35-Enzo Perez, 7-Oscar Cardozo, 18-Eduardo Salvio. (Additional reporting by Mark Elkington in Madrid, editing by Justin Palmer)