"I just had a jinxed day," said Lewis, who had just one fumble in his previous five games.
The Ravens got as close as 27-17 when Lewis scored on a 77-yard swing pass late in the third quarter and Matt Stover kicked a 26-yard field goal early in the fourth.
But the Saints answered with a 28-yard field goal by Carney and intercepted Blake to set up a 6-yard run by McAllister, boosting the margin to 37-17 with 2:57 left in the game.
Against his former team, Blake was 18-for-39 for 316 yards and two touchdowns. His performance, though, was marred by two interceptions and a fumble. He didn't get any support from his shaky receivers or Lewis (48 rushing yards).
"Honestly, if we don't make any turnovers, we win this football game," Blake said. "Everything they got, we gave them."
The Ravens, who dropped to 2-6 against winning teams, finish out the season against the Houston Texans, Cleveland Browns and Steelers. But by not taking care of business yesterday, the Ravens watched their flickering playoff hopes dim.
"The opportunity was on the table and everything was laying right in front of us and we didn't grab it," Heap said. "I think there is still a shot, although other things have to happen for us. If we can bounce back and get our heads back into it, we've got a shot to go somewhere."
Next for Ravens
Matchup:Ravens (6-7) vs. Houston Texans (4-9)
Site:Reliant Stadium, Houston
When:Sunday, 1 p.m.
TV/Radio:Ch. 13/WJFK (1300 AM), WQSR (102.7 FM)
Line:Ravens by 3