Wardlaw and Smith were awarded free kicks inside the final 90 seconds but both failed to score as the Saints fell to a 5.6 (36) to 5.5 (35) defeat in Ballarat on Sunday.
After a promising 3-0 start to the year, Nick Dal Santo's side have lost six of their past seven games.
It means they will miss the top eight and are still searching for their first finals appearance after five seasons in the competition.
Coach Nick Dal Santo is disappointed his side missed the finals after a great start to the season. (Rob Prezioso/AAP PHOTOS)
"Unfortunately in the last month or so we'd lost the opportunity to control our own destiny and it was going to come down to other teams anyway, so it wasn't really even about that today," Dal Santo said.
"In saying that, we knew that a win would've kept us in calculations in regard to next week.
"(We're all) disappointed a little bit by the result - and it's easy to measure yourself by that - but we had some really clear focuses coming into this game that we wanted to work on and we didn't get it done."
Adding to the Saints' woes, key defender Bianca Jakobsson had to be helped from the field before quarter-time with a serious left knee injury.
"It didn't look great, but it was down in the far pocket so it was a little bit difficult to see," Dal Santo said.
"We'll wait to get some clarity on that."
The Bulldogs are also well out of the finals picture this year, but have registered consecutive victories over the past two rounds after a horror 2-6 start.
We pulled off a thrilling one-point comeback win over Euro-Yroke in Ballarat on Sunday.— WesternBulldogs AFLW (@BulldogsW) � Read more:October 27, 2024
Jessica Fitzgerald starred for the Dogs, celebrating her 50-game milestone with 26 disposals, six clearances and two goals.
Deanna Berry also shone with 21 touches and five clearances. The skipper also kicked one of the best goals of the season with a brilliant snap from hard up against the boundary line under pressure from two opponents.
Nat Exon and Ashleigh Richards kicked two goals each for St Kilda, who led throughout the first half and stretched their advantage to 14 points early in the third quarter.
But the Bulldogs kicked the next three goals and led by one point at the 10-minute mark of the final term through a behind to Heidi Woodley, which was the final score of the game.
Nat Exon kicked two goals in St Kilda's heartbreaking one-point loss against the Bulldogs. (Joel Carrett/AAP PHOTOS)
Wardlaw (18 disposals, 11 hit-outs) impressed in the ruck and was gifted a chance to win it through a free kick paid against Alice Edmonds, but sprayed her shot badly from just inside 50 metres.
St Kilda had one last chance when Elisabeth Georgostathis was penalised for deliberate out of bounds, but Smith put her shot out on the full and the Bulldogs hung on.
"That was pretty special. I love playing with these girls and I was counting down the seconds to the siren," Fitzgerald told the Seven Network.
"It was really special and in Indigenous Round as well, there was so much to play for."
Both sides have 4-6 records and will end their seasons with games against finals-bound opponents next Sunday.
St Kilda host Brisbane at RSEA Park, while the Bulldogs travel west to take on Fremantle.
