The return of two suspended players and the absence of two others could prove to be a deciding factor in Wednesday's World Cup Group D clash between Australia and Serbia. Australia welcomes back arguably its best player in Tim Cahill, who missed last week's 1-1 draw with Ghana after being sent off in the 4-0 defeat by Germany in its opening match. Cahill is expected to tuck in just behind striker Brett Holman in a game it must win. If the Aussies find they need more firepower, coach Pim Verbeek might also be tempted to throw Josh Kennedy into the attack. “All through the qualifiers that's how we played virtually - me up front with Timmy just behind me, and I think in every game either he scored or I scored,” Kennedy said. “We have always worked quite well together and he's back now.” Serbia can call on central defender Aleksandar Lukovic, who was sent off in its opening 1-0 defeat by Ghana and suspended for the win over Germany by the same scoreline last Friday. “It is good to have Lukovic back as he will add steel in defense,” coach Radomir Antic said. But while those two players return to help their respective teams two other Australians are sidelined. Forward Harry Kewell is suspended having seen red against Ghana and teammate Craig Moore is out after picking up his second yellow card of the tournament in the same match. Scott Chipperfield is likely to replace Moore in defense. With just one point from two matches, the Aussies have only a slim chance of qualifying for the second round and have been pondering the mathematics that would take them through. “If Ghana beats Germany and we win by any score we're through, and if Germany really beat Ghana and we beat Serbia convincingly then we're still in it,” said captain Lucas Neill. “As a nation we should not give up because this team is not giving up.” Antic said Serbia's confidence was high after its first win over Germany in 37 years. With three points to their name, a draw would be enough for the Serbs if Germany lose and a win certainly would. “It's all in our hands now as victory would put us through to the knockout stage of the competition,” captain Dejan Stankovic said. Serbia will have to be careful not to pick up more yellow card if it does go though to the next round. Six of Antic's regular starters are already on yellows going into Wednesday's match at the Mbombela Stadium in Nelspruit.