World number one Rafael Nadal's quest for a 16th Grand Slam title will lead to a barrage of big serves when he battles South African Kevin Anderson in a conflict of styles at the US Open final on Sunday.
Both men are 31 years old but have little else in common.
Throughout the tournament, Spanish juggernaut Nadal has been playing the devastating brand of all-court tennis that won him a record-extending 10th French Open in June, mixing punishing groundstrokes and pinpoint serving with relentless defence.
Anderson, who will be playing in the first Grand Slam final of his career, relies heavily on his huge serve, which topped 135 miles per hour (217 kph) during his four-set battle against Pablo Carreno Busta in their semi-final on Friday.
The 6ft 8in (2.03m) world number 32 Anderson will be a big underdog against Nadal, who will contest his 23rd major final.
Head-to-head, Nadal has dropped only one set and won all four of their previous meetings. In their lone grand slam match at the 2015 Australian Open, the Spaniard won in straight sets.
With his path to the final eased by injuries to leading players, Anderson also became the lowest ranked Grand Slam finalist since Jo-Wilfried Tsonga's run to the 2008 Australian Open final when world number 38.
Nadal will be playing in his fourth US Open final, having won the title in 2010 and 2013.