Rodallega, who left Wigan Athletic on a free transfer this summer, netted his first goal in a Fulham shirt in the club's 1-0 win over MK Dons in a pre-season friendly on Tuesday.
"Before pre-season and any players coming in you would probably think it was a bit light [up front]," the Ealing Gazette quotes Sidwell as saying.
"But I don't think we're light at all up there now. Petric doesn't need many chances to score goals and Hugo has come in and scored. It's down to the rest of us to chip in with goals now.
"The gaffer (Martin Jol) is always looking for strikers to come in but if we start the season with what we've got it's not a problem."
Fulham's first game of the new Premier League season is a home fixture against Norwich City.