SAM Long knows the comparisons with Brazilian full-backs may have to be shelved for tonight’s visit of Peterborough United.

Oxford United host the Sky Bet League One leaders (7pm), who have won their last six games and scored 15 goals in the process.

U’s full-backs Long and Josh Ruffels were nicknamed the ‘Oxford Cafu and Roberto Carlos’, in honour of the great Brazilian duo, having contributed seven goals and eight assists between them this season.

But with the second-highest scorers in the division in town, the academy graduate is aware of his chief responsibility.

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Long, 26, said: “Ruffs and I pride ourselves on our defensive duties before anything else.

“I know we’ve had the ‘Oxford Cafu and Carlos’ this year, but we know first and foremost our job is to defend.

“We’re going to have to do a lot of that because they’re a very good attacking outfit.

“We know our job and we will try to join in (attacks) as much as we can as well.”

Peterborough’s main goal threat is Jonson Clarke-Harris, whose 21 goals in League One alone makes him the division’s top-scorer.

The forward’s late double against Wigan Athletic on Saturday – which turned a 1-0 defeat into a 2-1 victory – continued a run of nine strikes in his last seven games.

Posh’s attacking options also include Siriki Dembele, who scored in United’s league and Emirates FA Cup defeats to tonight’s opponents in October and November respectively, plus Sammie Szmodics, on ten for the season.

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“Their front line is probably as good as it comes in this division,” Long said.

“You always want to test yourself against the best players and if we want to be successful we need to beat the best teams.

“As it stands, they’re the best team in the division.

“If we won we could take some confidence and belief from that and hopefully put together another run like the one we were on a couple of weeks ago.”

United begin the game ninth in the table, just four points outside the play-off places, while Peterborough lead the division by four points.

U’s head coach Karl Robinson said: “I think they have the biggest threats.

“They have the ability on any given day to score a number of goals because of the quality they have at the top end of the pitch.

“I think they’ve found a consistency in the middle and the back four looks very solid as well.

“The league table tells you they’re the best team in the league, because they’re clear.”