Martin O'Neill has urged his Republic of Ireland players to seize the initiative by attacking Group D rivals Austria in their crunch clash at the Aviva Stadium.
The Boys in Green sit joint-top of the standings, locked level on 11 points with Serbia at the midway stage ahead of Sunday's visit of their fourth-placed opponents.
Ireland could temporarily move three clear should they see off Austria on home soil as they play a few hours before their direct rivals, but O'Neill has warned his charges that they cannot afford to drop their performance levels if they are to avoid slipping up.
"We just have to try to do our utmost. If we have done our utmost, then there is not much more I can ask," he told reporters. "I don't think that we've got the ability to carry players in the team. We have to really be at it all the time, and that's one of our strengths, I think. But if we drop off... we just can't afford to do that, let me put it that way.
"For us, we have really got to start strongly in the game. We're at home, we have to take the game to Austria and really be positive right from the start. Austria have the capability of causing us all sorts of problems and we have to be on the front foot if we can, but also aware of their dangerous players."
Ireland beat Austria 1-0 in the reverse fixture seven months ago, sealing the win through a James McClean strike in Vienna.
No Data Analysis info
