The 28-year-old is set to make his debut against Celtic tomorrow at Greenhill Road and Lennon has no doubt he'll add a bullish presence middle to front.
The versatile frontman completed his £35,000 move from Hamilton this morning after having first been identified as the ideal addition by Buddies No.2 TommyCraig.
Lennon said: "Dougie's arrival is the end of a long process. We wanted to bring someone to St Mirren who gave us that bit extra and something different to what we already had here.
"Dougie can give us options in terms of whether he plays just off our strikers or alongside. He has extensive SPL experience and he is a winner. It is great to add him to the squad."
Meanwhile, Marc McAusland is determined to make up for one of the Buddies' most painful defeats of the season when they face Neil Lennon's Hoops.
A Gary Hooper hat-trick helped Celtic rack up a 5-0 win at Parkhead, a wound that is still painful for McAulsland.
The defender owned up to a couple of glaring mistakes that day and has vowed to atone for those slip-ups tomorrow. He said: "I know I was at fault on a couple of occasions at Parkhead in the 5-0 defeat and I have held my hands up for that. I am really determined to help make up for that one.
"We know we are going to have to be a lot tighter in possession than we were at Celtic Park and that both times we have played them this season we have gift-wrapped them goals."
McAusland reckons the Saints' midweek win over Hamilton Accies in the Scottish Cup will have them in fine fettle after a demoralising hammering at Hearts last weekend.
The 23-year-old added: "After the Hearts defeat it was vital to get the clean sheet at Hamilton. We will not alter our passing game, but we have to make sure anything Celtic get, they earn."