Spurs face Slovenian side Maribor in search of their first win in the competition on Thursday.
And although Villas-Boas’ side will not face elimination should they fail to win at White Hart Lane, the Tottenham manager admits three points are a must.
“It’s reached the stage now where matches start to define the group, we’ll have a real idea of what could happen after this fixture,” said Villas-Boas.
“Win, lose or draw, it doesn’t mean that mathematically we’ll be in or out, but a win can make a big difference. We will still have to do our job in Rome and against Panathinaikos.
“Maribor’s game at Lazio was very competitive and to be fair, they could have got a better result [they lost 1-0]. They are a team with a winning mentality.
“We have to do our job. We hope to put on a good performance and try to get the three points.”
The Spurs manager also called on the Tottenham crowd to get behind the team after a disappointing 1-0 loss at home to Wigan Athletic last weekend.
“Positive emotion from the stands is very welcome,” he said.
“Our crowd has been amazing in their support for our players and they can make a difference when they are at their best, and that’s what we need.
“This team wants to get back to winning ways and we can only do it together.”
• Maribor got a first taste of English opposition last season, when they lost 2-1 at home and 1-0 away to Birmingham City in the Europa League group stage.
• Spurs’ only fixture against a Slovenian side prior to matchday three came in the 1995 Intertoto Cup group stage, when they won 2-1 at NK Rudar Velenje.
• Tottenham have only won two of their last seven European home games, with that run including defeats against Real Madrid CF (1-0) and PAOK (2-1).
• Maribor’s 3-0 triumph over Panathinaikos on matchday one was their first victory in seven Europa League group stage fixtures. They recorded a draw and five defeats in last season’s competition proper.
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