The Three Lions strolled to a comfortable victory in Serravalle and will hope to carry the momentum from the win into Tuesday's more crucial Group H qualifier against the current leaders.
Six different England players were on target in the triumph, with Jermain Defoe scoring a double and Alessandro Della Valle netting an own-goal, while Alex Oxlade-Chamberlain, Ashley Young, Frank Lampard, Wayne Rooney and Daniel Sturridge added to the haul.
Smalling admits he had little to do in the clinical success but feels his team-mates have made Roy Hodgson's job more difficult when he picks his team for Podgorica.
"We've got a very strong squad, it's well over 20 and I think a lot of people have put their cases forward for Tuesday because we know that's the big one," he told Sky Sports.
"It's great to see a lot of the lads just all chipping in. Wazza (Rooney) scored a great free-kick but you could see there's goals all around the team and the subs coming on as well so it was a good all-round performance."
England were 5-0 up at half-time and Smalling added: "It was one of those where you don't have too much to do but we started that first half flying with those first five goals.
"Even before the first goal I think we had four or five chances straight in front of their goal so it was great to see.
"We did carry on in the second half, when we knew it was probably going to be a bit more difficult. It was a good game overall."