Swansea City striker Fernando Llorente's form is "key" to their hopes of Premier League survival, says head coach Paul Clement.
The Spain international has scored five goals in his last six games to help the Swans pull five points clear of the relegation zone.
Four of those have been headers, and Clement believes his aerial prowess compares to the world's best players.
"Llorente is wonderful at heading the ball," he said.
Clement continued: "[Cristiano] Ronaldo is also fantastic, [Gareth] Bale also good from a striker perspective.
"You have to look at John Terry and Sergio Ramos, central defenders who always did so well when they went forward into the box.
"He [Llorente] is doing very well and he's proven to be a key player during this period."
Clement worked with Ronaldo, Bale and Ramos at Real Madrid, while he coached Terry during his time with Chelsea.
Since taking over at Swansea, the former Bayern Munich and Paris St-Germain assistant manager has overseen five wins from eight Premier League matches.
That run of results has lifted the Swans from the foot of the table to 16th place, and Llorente has been pivotal to their upturn in fortunes.
"He's scored five goals since I've been here - the two at Liverpool, one at Chelsea and then the two against Burnley," said Clement.
"What's helped him is he's getting good supply into the box, and that was very clear in the game against Burnley - not just the two that he scored but other opportunities he had as well.
"He's a very good player when you get crosses into the box for him."
Meanwhile, Swansea will be without right-back Kyle Naughton for Saturday's trip to Hull with what Clement described as a "minor" hamstring injury.
The 28-year-old is expected to return for the match at Bournemouth the following weekend.