Despite missing key players such as Michael Carrick, Steve Lomas and Ian Pearce through injury, and having to play youngsters Anton Ferdinand and Shaun Byrne at full-back, West Ham showed the class to overpower Atvidabergs.
Roeder said: "It's great to see Joe and Jermain come back in such a great frame of mind. They have trained really well and are doing everything I am asking of them.
"I was delighted with how the side played. We knew it would be tough but it was a really good work out for the players.
"There was a bit of rustiness in the side, but we will get that right over the next couple of weeks. It is a very young team out there and a few of them boys could not have imagined playing in the first-team during the summer."
Atvidabergs opened the scoring after 15 minutes, Blaise Mbemba putting the ball past David James.
Cole then netted a stunning equaliser on 31 minutes but Atvidabergs regained the lead 18 minutes later through Dan Burlin.
West Ham got back on level terms on 62 minutes when French striker Youssef Sofiane scored and Defoe added a third goal soon after.
The England Under-21 player grabbed his second on 75 minutes and Cole completed the rout with his 83rd-minute goal.
Meanwhile, Trevor Sinclair, sold by West Ham for £2.5million this week, made a losing debut for new club Manchester City as they went down 1-0 to Odense in Denmark.
