Sydney FC's hopes of securing the Premier's Plate have been dealt a blow with striker Shane Smeltz banned for the next three matches.

Smeltz was shown a straight red card late in the Sky Blues' 3-0 victory over his former club Wellington at Westpac Stadium on Sunday after lashing out with his foot at Ben Sigmund.

Shane Smeltz exchanges words with Andrew Durante after being shown a red card during the game against the Phoenix. Credit:Getty Images

Football Federation Australia's match review panel on Monday determined Smeltz had committed the offence of "assault on a player" and proposed the minimum sanction for the offence of two matches plus the regular one-match ban for having received a red card.

Sydney can ill afford any setbacks with the race to the top the tightest it has ever been with only two points separating the top five sides. Sydney sit just one point behind ladder leaders Phoenix and are level on points with both Melbourne Victory and Perth Glory with four games remaining.