London 2012 Olympic Games individual gold medalists Katie Ledecky and Dana Vollmer were victorious in the women’s 200-meter freestyle and 100m butterfly, respectively, Thursday to open the Arena Pro Swim Series at Mesa.

Ledecky (Bethesda, Md./Nation’s Capital Swim Club) held off fellow Olympian Allison Schmitt (Canton, Mich./North Baltimore Aquatic Club) down the stretch to win the women’s 200m free in 1 minutes, 55.71 seconds to Schmitt’s 1:56.52.

“(Coach) Bruce (Gemmell) wanted me to push it on the front half of the race, which I don’t do that much,” Ledecky said. “It was good practice and once I get some rest if I put the same thing together the first 100 it will be faster, just naturally.”

Vollmer (Granbury, Texas/California Aquatics) posted the fourth-fastest time in the world this year in the women’s 100m fly, touching in 56.94 for the win ahead of Kelsi Worrell (Mt. Holly, N.J./University of Louisville), who was second in 57.27.  

Olympian Conor Dwyer (Winnetka, Ill./Trojan Swim Club) earned the victory in the 200m free in 1:46.61, with fellow National Team member Katie Meili (Colleyville, Texas/SwimMAC Carolina) taking the women’s 100m breast win in 1:06.49.  

Other winners Thursday in Mesa included:

• National Junior Team member Sean Grieshop (Austin, Texas/Nitro Swimming) in the men’s 400m IM in 4:18.75
• Youssef El Kamash of Egypt in the men’s 100m breast in 1:01.31
• Katinka Hosszu of Hungary in the women’s 400m IM in 4:35.81

Held at Mesa’s Skyline Aquatic Center, the long-course meters meet continues through Saturday with daily prelims at 9 a.m. Pacific followed by finals at 5 p.m. 

Television coverage of April 15-16 finals from Mesa will air on NBC Sports Network on next-day delay, while NBC Sports Live Extra will stream April 15-16 finals live. A live webcast of the entire meet also will be available at usaswimming.org.

The Arena Pro Swim Series at Mesa is the fourth of seven stops of the 2015-16 Arena Pro Swim Series. As part of USA Swimming’s partnership with swimwear leader Arena, the circuit will feature a record $350,000 in overall prize money. Swimmers may earn awards for top-three finishes in all individual Olympic events across the series. At each meet, $1,000 will be provided for a first-place finish, $600 for second and $200 for third. In addition to the single-event prize money, the overall male and female winners of the season-long Series will earn a $10,000 bonus.

For the third consecutive season, longtime USA Swimming partner BMW will award the grand prize of a one-year lease of a BMW vehicle to the highest-scoring eligible male and female U.S. swimmers. 

Male and female overall Arena Pro Swim Series champions will be honored at the conclusion of the 2015-16 series based on the number of points accumulated throughout the seven meets. Participants will be awarded points in each individual Olympic event throughout the duration of the Series (Five points for first, three for second, one point for third place).