Tommy Paul serving during Day 5 of Rotterdam. (Getty Images)

Last week, two 500-level tournaments were played and a number of Americans had strong runs in both singles and doubles. Both men and women reached the quarterfinals or better around the world. With this week's tournaments over, here are the Americans who are making a splash three months into the season:

1

Tommy Paul

Quarterfinalist, ABN Amro World Tennis Tournament ATP 500

The strongest showing at a tournament so far in 2021, Tommy Paul reached the quarterfinals in Rotterdam before losing in straight sets to Marton Fucsovics. Before getting knocked out, the American took down two Top 50 players in the Netherlands. In 2021, Paul has not played past the second round of a tournament until now.

2

Jessica Pegula

Semifinalist, Qatar Total Open WTA 500

It was a wild ride for Jessica Pegula at this year's Qatar Open. After winning all three qualifying rounds, the American managed to reach the semifinals before falling to eventual champion Petra Kvitova in straight sets. Along the way, Pegula defeated the sixth seed Karolina Pliskova in a major upset. The 27-year-old now holds a career-high ranking of world No. 36.

3

Nicholas Monroe

Doubles, Argentina Open

Unfortunateny, it was a quick exit for Nicholas Monroe and partner Sitak at the Argentina Open. But the Tennis Channel analyst was still in high spirits before moving on to the Chile Open. Monroe managed to take the first set before failing to capitalize.

4

Nicole Melichar

Doubles Champion, Qatar Total Open WTA 500

Nicole Melichar and her partner Demi Schuurs took home the doubles title at the Qatar Open, beating three other teams along the way. They avoided dropping a set in the first two rounds before fighting for their lives in the semifinal and final, battling in grueling deciding sets that went to 10 games. 

5

Danielle Lao

Champion, ITF W25 Newport Beach

In an all-American final, Danielle Lao took down the fifth seed Claire Liu to secure her first title since June 2015. The last time Lao raised any title was when she defeated Brooke Austin in the Baton Rouge ITF tournament. This tournament victory is one of  the best wins of her career.