Tennis great Andy Roddick says he would only need 4 days to fix the serve of the upstart 20-year-old American who battled Novak Djokovic

• Jenson Brooksby, the 20-year-old who battled Novak Djokovic at the US Open, has a fairly weak serve.
• Andy Roddick said he could help Brooksby's serve in just 4 days working together.
• Brooksby has won many fans with his crafty game and many believe a serve would make him dangerous.

A week with Andy Roddick might bring Jenson Brooksby's game to a whole new level.

The 2o-year-old Brooksby momentarily took the tennis world by storm when he beat Novak Djokovic, 6-1, in the first set of their US Open match. Though Djokovic stormed back to win in four sets, wearing Brooksby down in the process, Brooksby's unorthodox, clever game captivated viewers.

The 99th-ranked player in the world, Brooksby has just one major flaw: a relatively weak serve in a game of big-hitters.

Throughout the broadcast, ESPN commentators John McEnroe and Brad Gilbert kept talking about how much more dangerous Brooksby could be if he could add 5-10 miles per hour to his serve.

On Twitter, Andy Roddick, the last American man to win the US Open, shared his thoughts on Brooksby's play, saying he could improve Brooksby's serve in four days.

-andyroddick (@andyroddick) September 7, 2021

-andyroddick (@andyroddick) September 7, 2021

Roddick, of course, was known as one of the game's most powerful servers during his career. He once hit a 155-mile-per-hour serve in 2004.

Brooksby has plenty of time to improve his serve. He only turned pro in January of 2021 and has since shot up the rankings, making it to the ATP Tour. He was set to play collegiate tennis for Baylor in 2020 but missed the entire season with injuries.

Brooksby's raw but clever game has won over a lot of big names in tennis. Roddick said he was in love.

-andyroddick (@andyroddick) September 7, 2021

Andy Murray watched Brooksby at the Citi Open in Washington D.C. earlier in August and came away impressed.

-Andy Murray (@andy_murray) August 6, 2021

Djokovic also praised his opponent.

"He's a young, talented player that is very crafty," Djokovic said via The Washington Post's Liz Clarke. "He's got the really all-around game."

According to the ATP, Djokovic added: "He's so crafty from the back of the court, and he's a very intelligent player, and he's only 20. There's a lot of time ahead of him."

The New York Times' Christopher Clarey also came away impressed, saying if Brooksby can improve his serve, he'll be a name to watch for years.

-Christopher Clarey (@christophclarey) September 7, 2021