ONE man has famously been described as having the heart of a chicken.

The other is one of the bravest, craziest, most irrepressible players on tour.

In those circumstances, you would normally expect the second man to beat the first when they play, and that is what happened in last year's second round when Nick Kyrgios fought back from two sets down and saved nine match points before beating Richard Gasquet. But, 12 months on, the fourth-round meeting of the Australian and the Frenchman on No 2 Court is not quite so straightforward as that.

For a start, Kyrgios, though courageous and driven, at 20 remains raw and inconsistent. And Gasquet, nine years his elder, has this year acquired a dash of fighting spirit to go with his artistry.

That fight was on display in the last round against Grigor Dimitrov, the man who ended Andy Murray's defence of his title in the quarter-finals last year. When the No 21 seed went two sets up on the Bulgarian, it was tempting to think "Aha, I see Gasquet's planning to lose in five again". But he maintained his high level of play and saw off Dimitrov in three.

If Gasquet plays as consistently well again, he will be favourite to win, because of the lapses to which Kyrgios is prone. But the Australian showed in the last round against Milos Raonic, which he won in four sets, that he is learning to minimise his dips in concentration. And he reached the quarter-final last year on his debut, so this is by no means unexplored territory for him.

"Serving is key," Kyrgios said when asked what it would take to beat Gasquet. "He's going to play solid from the ground - he's a magician from back there. I'm going to have to play the same type of tennis. I'm not going to change anything."

Only Kyrgios is changing, for the better. He still can't resist the odd brush with authority, but he is learning to let his tennis do the talking when it matters.

Given Kyrgios's prediction that his serve will be his most important, it is no surprise that Gasquet thinks returning will be the most critical aspect of his own game. "Most important is return of serve," he said.

"He has one of the best serves in the world. He has a big forehand. He's a tough opponent because he has such a great serve. And to return him on grass, it's very difficult." It should be the tie of the round.

The winner of the Gasquet-Kyrgios match will face either Stan Wawrinka or David Goffin in Wednesday's quarter-final, with French Open champion Wawrinka being a strong favourite to beat the Belgian No 16 seed. The Swiss player, who also won the Australian Open last year, is now one of only six active players to have won two or more majors - and one of the others, Lleyton Hewitt, is on the verge of retirement.

Given that statistic, Wawrinka, seeded four here, is entitled to regard himself as just as much a part of the top echelon of tennis as Andy Murray, who has also won two Grand Slams. And given Rafael Nadal's current slump, those two are arguably ahead of the Spaniard, and not too far behind Roger Federer and Novak Djokovic, when it comes to their current stature in the game.

In other words, Wawrinka is a serious contender here. Goffin has been playing calm, controlled tennis, but he will need to find a more explosive side to his play if he is to upset the odds.

Djokovic, who lost to Wawrinka in that Roland Garros final, meets Kevin Anderson of South Africa for a place in the last eight. Anderson's serve makes him a real danger on grass, but the defending champion is one of the best returners in the game, possibly second only to Murray. Anderson could win a set if one goes to a tiebreak, but the top seed's greater versatility should see him through.

If he does progress, Djokovic will next play either Marin Cilic, the No 9 seed from Croatia, or the unseeded American Denis Kudla. Cilic looked set for a war of attrition in the last round against another American, John Isner, when their fourth-round match recommenced on Saturday at 10-10 in the final set - after all, Isner was the winner of the longest match in tennis history, beating Nicolas Mahut 70-68 in the decider here five years ago. But, surprisingly, the match was over in no time, as Cilic took the first two games to give himself one of the shortest possible days at the office.

Kudla, a 22-year-old who was born in Kiev but moved to the United States as an infant, has never previously got past the second round of a major. He has got this far with two five-set wins and one in four sets, and although he is fast improving, he will do well to take Cilic the distance.

Similarly, at the bottom of the draw, Roberto Bautista Agut will need inspiration and more than a little good fortune when he takes on Federer. The winner of that match will then play either Tomas Berdych or Gilles Simon, the Nos 6 and 12 seeds respectively whose meeting on Court No 2 could be the closest contest of the round.