"We competed for 65 minutes at a very high level," Hitchcock said. "We played a heck of a hockey game."
While Fasth is soaring, St. Louis' Brian Elliott continued to struggle. After leading the NHL in GAA and save percentage last season, Elliott was 39th and 42nd in those categories before Saturday.
His numbers got worse after he allowed five goals on 23 shots to the Ducks.
Elliott gave up a goal to Ryan on Anaheim's first shot at 11:09 of the first period. He appeared to settle down after that, as St. Louis built a 3-1 lead.
But the Ducks wiped out their deficit and took their first lead by scoring three times on three shots in a span of 2:21 in the second period.
Selanne started the run when he put in a deflection with Elliott out of position at 12:40. Just 45 seconds later, Cogliano scored. Ryan then beat Elliott at 14:21 to make it 4-3.
St. Louis trailed 5-4 when Stewart tied the game with a power-play goal at 15:26 of the third.
NOTES: Blues D Wade Redden was presented with a silver stick and a watch before the game in honor of his becoming the 280th NHL player to play in 1,000 games. Redden reached the milestone Thursday against Detroit. ... Anaheim is 2-1 on its six-game road trip. ... St. Louis announced that forward Jamie Langenbrunner will need hip surgery and will miss the rest of the season.