Watson helps around as Cowan stakes his claim

Shane Watson's hopes of playing in the Boxing Day Test suffered a set-back as he failed to take part in the opening day of Australia's batting camp here on Tuesday while all-rounder Dan Christian and Tasmania's opening batsman Ed Cowan moved closer to making a Test debut.

Instead of batting at the Melbourne Cricket Ground (MCG) nets, Watson, who is suffering from calf and hamstring injuries, helped assistant coach Justin Langer feed balls into the bowling machine and then hit the gym. But he couldn't take part in any of the drills designed by Cricket Australia (CA) to fine-tune its top order for the series-opener against India.

Watson failed to take part in the opening day of Australia's batting camp, while Cowan scored a ton against India.

Watson has already said that he won't bowl in the Boxing Day Test but his chances to play as an opening batsman is also fading as he makes a slow recovery from hamstring and calf injuries.

Cowan made a strong case to open the batting on Boxing Day with 109 for a Cricket Australia Chairman's XI against the Indians. The 29-year-old has made four hundreds, including Tuesday's century, this summer. He was faultless against India and had also struck 145 against New Zealand playing for Australia A last month. He has also a heavy first-class average of 54.12 this year.

"The biggest challenge is being able to make the game a bat on ball contest and block out 90,000 people and the occasion of having grown up watching Boxing Day, the ritual which is so very Australian," Cowan was quoted as saying by The Sydney Morning Herald.

"That would be the biggest challenge. I would be very confident about the batting stuff but you don't know until you try it." Cowan admitted his tons against New Zealand and India on batting friendly Allan Border Field and Manuka, have given him invaluable self-belief.

"As a state cricketer that's the pinnacle, to see international superstars to play against them and to benchmark yourself against them. To be able to score some runs has been a big confidence boost to know you're not that far off the running," he said.

Cowan's place in the side depends on Shane Watson's fitness while Australian coach Mickey Arthur hinted that he prefers Dan Christian as an addition to the batting line-up.

"It's almost as if you play with 12 players when you play with an all-rounder, so our preference for balance of the team is always to try and have an all-rounder. If we've got one that we think is capable of doing the job, we'll play him," Arthur was quoted as saying by the newspaper.

Arthur is one of five selectors, including captain Michael Clarke, who will name a Boxing Day Test squad on Wednesday. Arthur said injuries to key players may force them to unveil an expanded squad of 13.

Ricky Ponting is sure to be named in the squad, but Arthur said he and Mike Hussey cannot take their place for granted.