Hoops captain Brown has declared he wants to play in both of the national team's World Cup qualifiers against Wales on Friday and Belgium a week tonight.

The midfielder missed our opening Group A games against Serbia and Macedonia due to a hip problem that could ultimately require surgery.

And he is desperate to breathe life into our bid to make the finals in Brazil in 2014 by helping Scotland to victory in Cardiff on Friday night and then in Brussels next week.

However, Lennon was under the impression the 27-year-old, who took painkillers to play in the Champions League last week, would only be used in one of the matches due to his condition.

The Irishman is keen for his players to benefit from being involved in international football – but has one eye on a massive European double-header against Barcelona.

Dundee United manager Houston, though, has told his Celtic counterpart Brown will not be risked unless Scotland medical staff are completely satisfied he is in tip-top shape.

"Scott has had problems, there is no doubt about that, but if he is confident that he can manage both games then who are we to argue," he said at the Scotland base.

"If he is available and he feels good then fine. But we certainly wouldn't play him if he didn't feel right for the second game having played the first one.

"We need legs in the team. It is a short turnover and we will take advice from the physios, the doctors and, most importantly, from Scott himself."

Having badly missed Brown in the opening two games of the campaign, both of which ended in disappointing draws, Houston is pleased to see the Celtic man back in the Scotland squad.

He is, too, pleased he has been joined by Manchester United midfielder Darren Fletcher and on-form Sunderland striker Steven Fletcher.

"They have strengthened the squad," he said. "They bring experience to the team. We need every player we can just now to get some good results.

"Darren is a quality player who has played many, many internationals with Scotland and European matches with Manchester United.

"Steven is scoring goals in the Barclays Premier League just now. He is scoring goals at a new club, and we are delighted to have him here. It is nice to see him back.

"Scott brings enthusiasm, a tigerish attitude in the middle of the park and he fears nobody. He does a good job for the team. It is nice to have them all aboard."

Houston has dismissed suggestions Scotland boss Craig Levein has to pick Steven Fletcher after healing his rift with the Sunderland player.

Levein last month phoned the former Hibs, Burnley and Wolves player, who has scored five goals in the English top flight this season, to end the stand-off between the pair.

"It is too early to say whether Steven will play on Friday, but it won't be awkward if we don't play him," he said. "He is in the squad and he is happy to be in the squad."

Houston has no fears about Darren Fletcher's ability to play a full part in these crucial matches despite his lengthy absence from the Manchester United and Scotland sides.

The 58-times capped 28-year-old took a complete break from football back in December last year due to ulcerative colitis and only returned to action with United last month.

The coach said: "We trained yesterday and Darren, along with Alan Hutton, who hasn't been playing, and Jamie Mackie, did extra towards the end. It is fantastic to have him back. He is looking fit and strong.

"Darren and Scott Brown are key players who would, if they had been fit, have started our last games against Serbia and Macedonia. Having those two guys is brilliant for us and important. It gives us more quality."

Meanwhile, the assistant manager has expressed confidence that Hutton will be able to cope with these qualifiers despite his continuing absence from the Aston Villa first team.

He said: "Alan Hutton's experience can get him through games. I thought against Australia, when he wasn't in the Aston Villa team, he was excellent. I also thought he was decent in our last two games.

"You are looking for his experience to get him through games. His fitness levels, which we monitor regularly, are looking good. The fact he has not been playing are a slight, but not a major, worry.

"We are all determined to go to Wales and get as many points as we can from the game there – and then the game against Belgium after that."