(From top) Kovac, Ronaldo, Behrami, Malouda

Bad Brueckenau: Croatia are optimistic that captain Niko Kovac will have recovered from a rib injury in time to play against Japan on Sunday, the team doctor said on Thursday.

Kovac came off after 40 minutes of Tuesday’s match against Brazil following a heavy challenge from Ze Roberto. He was present at Thursday morning training, but broke off after about 15 minutes.

“Niko Kovac had treatment and feels much better, although he is still in pain. I’m optimistic he will play,” team doctor Zoran Bahtijarevic told a news conference.

Croatia defender Josip Simunic, who plays with Kovac at Hertha Berlin, emphasised the captain’s importance to the team.

“A couple of years ago there was speculation that he was not vital. He is always important as he always gives 100 per cent. You saw he left the pitch and four minutes later we let in a goal,” Simunic said, referring to Kaka’s 44th minute strike.

Croatia are also optimistic that striker Ivica Olic, who came on as a substitute in the second half of Tuesday’s match, would be fit for the Japan match. He has been receiving treatment in Berlin for a strain to his left thigh.

Portuguese winger Cristiano Ronaldo trained separately in Marienfeld on Thursday, casting doubt on whether he would be fit for his country’s next group D game against Iran.

The player, who appeared upset when he was substituted during Sunday’s 1-0 win over Angola and who completed just 15 minutes of training on Wednesday, limited his session to short runs and exercises with a physiotherapist.

Asked about the situation with Ronaldo, playmaker Luis Figo was tight-lipped. “You will have to ask the doctor about Ronaldo. I think he’s okay, he just didn’t train because of a small problem.”

France midfielder Florent Malouda is fit to face South Korea on Sunday. France coach Raymond Domenech said Malouda has fully recovered from injury, according to a report from Hamelin.

“He is apt to play,” Domenech said on Thursday. “He has trained the same as everyone else.”

Domenech would not say what injury Malouda had recovered from, and has ordered his medical staff not to comment on any injuries during the World Cup.

Sylvain Wiltord left the field in the 83rd minute of France’s 0-0 draw against Switzerland. An ice pack was immediately put on his knee, but it appears the Lyon midfielder suffered no damage. “There are no worries, no injuries, everyone is operational,” Domenech said.

Switzerland will wait until next week to decide if injured defender Valon Behrami should remain with the squad. Team doctors said on Thursday in Bad Bertrich that Behrami could be sent home early because of a groin injury that has plagued the player since the start of Switzerland’s World Cup preparations.

An MRI scan conducted later in the day has since given the team cause for more hope.

“Today’s scan confirmed that there has been at least no worsening of the injury,” Swiss team spokesman Pierre Benoit told reporters.

“Behrami will undergo further tests and will not train with the team for the next two or three days, but there will no be final decision until next week.”