The Thrashers outshot the Hurricanes 42-18 but were turned away time after time by Ward, the unlikely star of Carolina's run to the Stanley Cup championship last season.
Whitney's second goal gave Carolina a 4-1 lead and prompted Thrashers coach Bob Hartley to yank Lehtonen with 4:51 left in the second period. He stopped only nine of 13 shots.
Johan Hedberg went the rest of the way in the Atlanta nets and was barely tested, facing just five shots while Ward was sprawling all over the ice at the other end.
Marian Hossa had his NHL-leading 11th goal on a power play but could have a much bigger game if not for Ward, who turned aside 15 other shots by Atlanta's top scorer. Hossa, who scored his 500th career point, had nearly as many shots himself as the Hurricanes.
Ilya Kovalchuk redirected a shot from the point early in the third but Ward still managed to smother it, prompting Kovalchuk to look toward the roof in disgust.
The Thrashers went 1-for-10 on the power play, failing to convert a lengthy two-man advantage late in the second.
Carolina has won all three meetings between the Southeast Division rivals this season. The first two were much closer, with Carolina winning 4-3 on a goal in the last second of regulation, then prevailing 5-4 in overtime.
This time, the Hurricanes didn't need a dramatic goal at the end. Their top line of Whitney, Brind'Amour and Erik Cole was especially dominant, accounting for all but one of the goals.
Whitney and Scott Walker scored 40 seconds apart in the first period. After Hossa pulled the Thrashers within a goal at 3:58 of the second, Brind'Amour and Whitney gave the Hurricanes a commanding lead.
During a delayed penalty against Atlanta, Cole worked hard to keep the puck in behind the net, then Whitney picked it up and whipped a pass to Brind'Amour in front. He fired a shot over Lehtonen's glove in the top right corner.
Then, right after Carolina killed off a penalty, Whitney cut in front of the net and ripped a low shot that got by Lehtonen's right skate. That was the end of the night for Atlanta's goalie, who took a seat at the end of the bench.
Vitaly Vishnevski gave Atlanta a faint hope, scoring a backhander that deflected off a Carolina player's stick with 12 1/2 minutes left. But Brind'Amour scored an empty-netter with 1:26 remaining to clinch it.
Notes: Hossa has scored eight of his 11 goals on the power play. ... Atlanta D Niclas Havelid and Carolina D Tim Gleason both sat out their first game of the season. ... The Thrashers got chippy in the final minute. Atlanta's Scott Mellanby received a 10-minute misconduct, then J.P. Vigier of the Thrashers and Carolina's Craig Adams got into a brief fight along the boards before the linesmen jumped in quickly to keep thing from getting out of hand.