Portugal coach Paulo Bento is weighing up whether to gamble on both Cristiano Ronaldo and Pepe in Tuesday's friendly with the Republic of Ireland, as the star duo race to be fit for the World Cup.

The Brazilian showpiece begins on Thursday and the Portuguese face the strongly fancied Germany on June 16 in the so-called "Group of Death," which also includes Ghana and the USA.

But neither of the Real Madrid aces have been able to play a full part in Portugal's preparations and have missed the last two warm-up games, a barely deserved 1-0 win over Mexico and a dull 0-0 draw with Greece.

Bento would have hoped that the game against the Irish in New Jersey, in the United States, would be a final chance to fine-tune his squad with the Germany clash less than a week away.

But instead it has taken on extra significance and all eyes will be on how long -- if at all -- Bento gives Ronaldo, Pepe and Raul Meireles, another key player whose preparations have been disrupted by injury.

"Two of them trained on Saturday and Sunday and Pepe will train today," Bento revealed on Monday.

"Their situation will depend on how they respond to training and we'll see what our decision will be for tomorrow's match.

"It's always difficult to train without the full squad and it's always difficult to prepare for a big match like the German one without all the players fit."

Ronaldo, 29, who has scored 49 goals in 110 matches for Portugal, has been struggling with left thigh and knee problems, while centre back Pepe has had a calf injury.

Bento said he would have no qualms about risking any of the influential trio against Ireland, who did not qualify for Brazil and are rebuilding under Martin O'Neill.

"We accept that British teams usually play aggressively and are very strong in the duels, but we won't be thinking about that (when it comes to picking Tuesday's side)," Bento told reporters.

Portugal have struggled in attack in Ronaldo's absence, failing to score against Greece and then needing an injury-time winner from defender Bruno Alves to beat Mexico.

Bento has limited top-quality striking options if Ronaldo is not fit and firing.

He could go for the inexperienced Eder, but he has not scored in eight outings and missed several chances against Mexico, representing something of a gamble for the usually conservative Bento.

O'Neill and his skipper Robbie Keane know that the Irish will be very much the support act to the Ronaldo show, but said they were relishing facing him in front of what is expected to be a 50,000 crowd.

"He's one of the top two players in the world (with Lionel Messi) and he's a brilliant, brilliant player," said O'Neill.

"It's good for us to play against him. The players want him to play so they can test themselves."

Keane, who now plays in the US for LA Galaxy after stints in the English Premier League and Italy, added: "He and Messi are clearly the best in the world and every player wants to play against the best.

"And it's a good test to play against him, so we certainly hope he does play."

Striker Keane, 33, dispeled any notion that his side would simply roll over.

"You want to play every game and you want to win every game. Winning is a habit. It's going to be a big, big test against a great team."