Lewis Hamilton is driving as well as ever, according to Mercedes co-team boss Paddy Lowe.
The Briton, who won his only World Championship with McLaren in 2008, is targeting a third successive Grand Prix win in China this weekend.
"We have seen Lewis arrive this season on top of his game," Lowe told BBC Radio 5 live. "He is fit physically. His mental state is brilliant.
"That gives us great promise for the rest of the year."
After winning the world title in only his second season in Formula 1, Hamilton never finished higher than fourth in his four subsequent campaigns at McLaren.
He chose to leave the team that had nurtured him since the age of 13 at the end of 2012, but could only finish fourth with Mercedes last season, 208 points adrift of Red Bull's champion Sebastian Vettel.
This season, however, Hamilton has taken advantage of a revamped car to win in Malaysia and Bahrain, closing to within 11 points of team-mate Nico Rosberg, who leads the standings.
Lowe, who has worked with Hamilton for his whole Formula 1 career, expects the 29-year-old to go from strength to strength.
"His experience over all the years he has spent in F1 means he has all the ingredients to have a fantastic season," said Lowe,
"We saw that in both qualifying sessions this year and the race in Malaysia. We saw the old Lewis at work there, in total command of the race."
Hamilton and Rosberg went wheel to wheel during the last race in Bahrain, with Hamilton just holding on to win.
Lowe said Mercedes will continue to encourage their drivers to entertain fans.
"Our philosophy is that they race each other without any constraint between them," he added.
"We want to provide a good show in that respect and hopefully we can get one of them to take the championship if we can do it."