He was then sent to Serie A side U.C. Sampdoria for a total fee of 4 billion lira. Playing alongside talented players such as Gianluca Vialli, Roberto Mancini, Pietro Vierchowod, Gianluca Pagliuca, and Ruud Gullit, under manager Vujadin Boskov, Lombardo won several domestic and continental trophies with Sampdoria, such as Serie A, the Coppa Italia, the Italian Super Cup, and the Cup Winners' Cup. In the 1988–89 season, he picked up medals for the Coppa Italia in 1989, facing a rejuvenated Napoli side with legendary Argentine attacking midfielder Diego Maradona, only to defeat the "Partenopei" 4–0. In 1990, he lifted his side to victory in the Cup Winners' Cup, retaining impressive wins against Borussia Dortmund, AS Monaco, and R.S.C. Anderlecht in the final.