Michael Clarke fails to train in Delhi Australia captain Michael Clarke didn't train on Thursday because of a back injury and his hopes of playing in Friday's fourth Test against India appear to be over. Clarke's no-show in the nets at Delhi's Feroz Shah Kotla Stadium led to all sorts of top-level talks as selector-on-duty Rod Marsh, high-performance manager Pat Howard and coach/selector Mickey Arthur buzzed around the group of players, dropping some, recalling others. It's believed up to five changes could be on the cards for Friday's dead-rubber match as Australia seek to avoid a four-nil whitewash at the hands of MS Dhoni's side. While Clarke's absence will be keenly felt not as only as a leader but as the team's leading scorer in the series, Clarke is confident Watson can produce a big innings after scoring only 77 runs in the first two Tests. He plays his own way. He's very aggressive and he's a match winner for us and I love seeing him play that way," Clarke said on Thursday. I think it's just a matter of time. I wouldn't be surprised if he walks out in this Test and comes out with a bang with a hundred to finish this tour. Watson has scored only two hundreds in his 40-Test career and has averaged only 25.20 in 13 matches since being appointed vice-captain to Clarke. Only last week Watson was in the sin bin, banned for match for failing to deliver a homework assignment on time. Watson was given leave to attend the birth of his first child in Sydney and was furious at his suspension, describing it as harsh. The 31-year-old, who makes a handsome living in the Indian Premier League and is a star in short-form international cricket, said he was considering his future at Test level. Howard labelled Watson a good team man "sometimes." This prompted Watson to slam ex-rugby international Howard, saying he hadn't been involved in cricket for long. However both say they are on the same page now. Clarke, Arthur and team manager Gavin Dovey handed out last week's `homeworkgate' bans to Watson, Mitchell Johnson, Usman Khawaja and James Pattinson. Watson, in-form quick Pattinson and possibly also Johnson now appear set to play in the fourth Test. Offspinner Glenn Maxwell is pushing hard for a recall while wicketkeeper Matthew Wade is likely to play after recovering from an ankle injury. India lead the four-match series three-nil.