The striker, 30, signed for the Lions last week and made his debut in Saturday’s 4-0 win at Concord Rangers.
Millwall head to Fulham on August 21, in what will be their fourth fixture of the 2019-20 campaign.
The Cottagers secured captain Tom Cairney on a new contract – a statement of intent that they are looking to bounce back from Premier League relegation.
And the Lions targetman was talking before Fulham also announced Aleksandar Mitrovic had penned an extension on Sunday until 2024.
“I’m really good friends with Tom,” said Smith. “They’ll be one of the stronger teams in the league, without a shadow of a doubt.
“If you look at their squad they have not lost much, if any, from the Premier League.
“There are a few big teams in there but when I was at Fulham we beat Newcastle on the opening day – and they went on to walk the league.
“Sometimes it’s best to get the big ones early before they get momentum going. It’s not always the worst thing.
“There really are no easy games – anyone can beat anyone on their day. It’s all about application, concentration and making sure we’re prepared for every match.”
PICTURE BY BRIAN TONKS