The pair came together for Hull's 1-1 draw with Tottenham on Saturday.
Bruce beamed: "Long and Jelavic led from the front.
"I thought to myself 'I wouldn't want to be playing against them two' because they did everything they could to score a goal.
"I think we've added that extra bit of quality to the squad.
"No disrespect to the squad we had before but these are far different to what we've had before. Let's hope so, that was the plan anyway.
"That's why I went to the chairman and knocked on the door. Let's hope it works."