Romelu Lukaku is harder to mark than Zlatan Ibrahimovic, according to former AC Milan defender Alessandro Costacurta.

Lukaku has been in fine form for Inter this season, playing a key role in helping Antonio Conte’s side reach the top of Serie A for the first time last weekend.

Both forwards are expected to play pivotal roles for their teams in Sunday’s crucial Milan derby at San Siro.

“‘When you have someone 1.9m tall with Lukaku’s speed in front of you, like against Lazio, I get the impression he is unstoppable,” Costacurta remarked in an interview with Italian broadcaster Sky Sport Italia today.

“Ibrahimovic is better at bringing others into play but perhaps because of how Inter play now, Lukaku could be more irritating for defenders than Ibrahimovic.

The Belgian national team forward has scored 22 goals in 29 appearances across all competitions to date and has also provided four assists for his teammates whilst out on the pitch.

The 27-year-old is Inter’s top goal scorer this season and is also the joint top scorer in Serie A alongside Juventus’ Cristiano Ronaldo with 16 league goals.

Former Nerazzurri goalkeeper Ivano Bordon has tipped Lukaku to be Sunday’s match-winner for Conte’s team.