Andy Roddick (1.67) v Marin Cilic (2.49)

Roddick and Cilic have split their two previous meetings one win apiece, with Cilic winning their most recent match back in 2008.

They also came into this tournament with very similar form having won their respective warm-up events (Cilic winning in Chennai and Roddick in Brisbane respectively) and then having a week off.

Roddick finished last season early after a knee injury in Shanghai, although before that he’d suffered a couple of shock defeats. Roddick is a four-time semi-finalist here and has won seven of his 12 matches against players ranked 5-15 since the 2008 US Open. However, defeats last summer to big-hitters Juan Martin Del Potro, Sam Querrey, and John Isner suggest this will not be an easy matchup for him. Having played a tough five setter in his last round against another big hitter the American’s fitness will also face its most significant test since his injury.

Similarly to Roddick, Cilic is on a nine-match winning streak. However, the Croat’s strong form dates further back, to his quarter-final appearance at the US Open, and he has now won 21 of his last 26 matches during which he has won three of four matches against players in the top four in the world. Moreover, he has won six of his last 10 matches against players ranked 4-14, and is improving.

With both players having been pushed to a fifth set in their previous match it is worth noting that both men have excellent records at the Grand Slams following a five set win, with Roddick winning seven of nine such matches and Cilic four of five.

With so little splitting these players we believe the match is a 50/50 call and that the value lies with Cilic.

Recommendation: Cilic to win at 2.49, BWin

Andy Murray (1.85) v Rafael Nadal (2.1)

Nadal leads the head-to-head by seven wins to three although that narrows to four wins to three on hard courts, while Murray has won three of their last five meetings, although he has dropped a set on each occasion.

Murray has had the most comfortable path through to the quarters of any player and is yet to drop a set. The Scot has an excellent record against top 10 players having won 21 of his last 30 such matches including going W17-L4 on hard courts.

Nadal has managed to beat only two top 10 players since his return from injury last summer, and those were against the lower ranked Jo-Wilfried Tsonga and Robin Soderling (in an exhibition), while he has lost 10 such matches with nine defeats in straight sets. The Spaniard appears to have returned to some form at the start of this year, although he began to look vulnerable when Philipp Kohlschreiber put him under pressure in the third round and the German had 15 break points during that four set match.

Since 1990 there have been 17 quarter-finals at the Australian Open between two top-eight seeds and just one of them has been settled by fewer than four games difference. Nadal has been improving, but given his recent record against top 10 players and Murray’s impressive form so far we expect the Scot to prevail.

Recommendation: Murray to win -2.5 games at 2.25, Sky Bet