The Saints were one of the busier clubs on the final day of the AFL's trade period with Dennis-Lane leaving Sydney for pick 47, while Jamie Cripps went to West Coast along with pick 46, with the Eagles giving picks 41 and 44 to St Kilda.
But St Kilda failed to gain Mitch Brown in any trade with West Coast although Saints' list manager Ameet Bains declared they could not have done any more to bring the 23-year-old defender to the club.
"Very close, very close, so from our members and fans' point of view, I want them to know that the club tried everything we could and it was a very live proposition even late today but unfortunately we couldn't get it done," Bains said after Friday's trade deadline.
St Kilda head of football Chris Pelchen added Brown had definitely wanted to move to Victoria but the Saints claimed they were not disappointed West Coast would not allow the deal to be completed.
"Look we made several offers to West Coast in the last couple of hours to try and get Mitch across the line," Pelchen said.
"There was no doubt Mitch wanted to play with us but we respect he's a contracted player and the Eagles declined."
West Coast recruiting manager Rohan O'Brien said Brown was a required player at the club, especially as skipper and fellow defender Darren Glass nears retirement.
"They (St Kilda) came a number of times all the way through, and they were obviously very keen to get him (Brown) in. But they understood our position," O'Brien told the AFL website.
"St Kilda were very fair all the way through with what they did, but we were keen to keep Mitch and hopefully he'll be with us for a number of years to come."
Bains added Dennis-Lane had been brought to the Saints due to having previously worked with Saints coach Scott Watters at WAFL club Subiaco.
And Bains said he believed Dennis-Lane would definitely be a boost to the Saints despite the club's long list of small forwards such as Stephen Milne, Ahmed Saad and Terry Milera.
"I think it's important to note that some of those guys (Milera and Saad) can play further up the ground, particularly once they've got another pre-season under their belt," Bains said.
"So he just gives us the flexibility to allow some of those other guys to do that."
Meanwhile, Melbourne list manager Tim Harrington hinted that St Kilda's busy final day of trading might have cost the Demons a deal to secure Saints midfielder Farren Ray.
"I think we were very close," Harrington said.
"The Saints had a fair bit to juggle in the end, so it just didn't quite get done."