Tour de France 2012: Ones to watch

Bradley Wiggins
Bradley Wiggins is vying to become the first British rider to win the Tour de France. The Team Sky rider is yet to finish on the podium, having finished fourth in 2009, but he is among the favourites departing from Liege on the 3,500km race to Paris.
Cadel Evans
Australia's Cadel Evans became the first rider from his country to win the Tour last year when he held off the challenge of Andy Schleck, who misses this year's edition through injury. The 35-year-old finished third in the Criterium du Dauphine behind winner Wiggins earlier in June.
Ryder Hesjedal
Ryder Hesjedal became the first Canadian to win a Grand Tour when he won the Giro d'Italia by just 16 seconds back in May. Whether he will be jaded by his efforts remains to be seen. He has a best finish of sixth in the 2010 Tour de France and is an accomplished climber and time-trialist.
Frank Schleck
Andy Schleck may not be around this year but his elder brother and RadioShack-Nissan-Trek team-mate Frank is. The 32-year-old, who is a specialist climber, finished third last year - the first time siblings had shared the podium - but his hopes may be thwarted by the 100km or so of time trialling in this year's race.
Vincenzo Nibali
Italy's Vincenzo Nibali is a decent all-rounder, having won the 2010 Vuelta a Espana without winning a stage. The 27-year-old finished consistently high in the placings on summit finishes and in the two time trials. This is his third Tour tilt, having finished 20th in 2008 and seventh in 2009.
Mark Cavendish
Britain's sprint specialist Mark Cavendish is the defending green points jersey champion. He switched to Team Sky in the off-season and will be supporting Wiggins in his quest for yellow. The world road race champion has lost weight, and as a consequence speed, to prepare for the Olympics but he will still be a force.
Peter Sagan
Slovakia's Peter Sagan is the new kid on the sprinting block. The 22-year-old is making his Tour debut and is favourite to win the green jersey. He has been in fine form this year, winning five stages at the Tour of California, including the first four.
Pierre Rolland and Thomas Voeckler
French hopes appear to lie with Europcar duo Pierre Rolland (left) and Thomas Voeckler. Rolland won the white jersey as best young rider in 2011, claiming a summit victory on Alpe d'Huez, while Voeckler spent 10 days in yellow to the delight of the partisan home support before finishing fourth overall.
Samuel Sanchez
Spain's Samuel Sanchez was among the favourites last year but a number of crashes saw him lose time. Compensation came in the form of the King of the Mountains jersey as he climbed to fifth overall. A sixth in 2008 and third in 2009 means the 34-year-old, who won the 2008 Olympic road race, cannot be ruled out.
David Millar
David Millar returns for an 11th Tour. The 35-year-old, who served a two-year ban for doping, has never finished inside the top 50 but is one of only four Brits, along with Tom Simpson, Sean Yates and Chris Boardman, to have worn the yellow jersey. Should feature in the time trials and/or on a breakaway.
Chris Froome
Chris Froome leapt to prominence at the 2011 Vuelta a Espana, wearing the race leaders' red jersey on stage 11. The British rider eventually finished second, one place ahead of Team Sky colleague Wiggins. He will help Wiggins in the mountains and could step up should his team leader falter.
Steve Cummings
Steve Cummings won Olympic silver on the track with Wiggins in 2004 and was part of the Team Sky set-up in 2010 but he switched to BMC Racing last year, the team of defending champion Evans. He was second in last year's Tour of Britain and is racing after recovering from breaking his pelvis in February.