Emma Hayes wasted no time shaking things up with the U.S. women's national team.

Her second day on the job, Hayes moved longtime defender Crystal Dunn to forward on the roster for two upcoming friendlies against South Korea. She also bypassed Lynn Williams, who on Sunday became the NSWL’s all-time leading scorer, and gave Washington Spirit midfielder Hal Hershfelt her first national team call-up at any level.

“I can’t wait to get into camp. We know it’s a short turnaround and we have a lot of work to do, but I’m fully focused on making sure that the performances are at the levels that are required to compete,” Hayes said in a statement.

“I expect complete commitment from everyone to absorb very quickly the things that I value as the most important so that we can compete this summer,” she added. “I know they are a highly coachable group and I’m looking forward to challenging them. It’s time to go to work.”

The USWNT will play South Korea June 1 in Commerce City, Colo., and again June 4 in St. Paul, Minn. They are the last two games before Hayes announces the 18-person roster for the Paris Olympics.

U.S. Soccer hired Hayes in November despite knowing she wasn’t available to take over the USWNT until this week. She’s one of the top coaches, for club or country, in the women’s game, and on Saturday she led Chelsea to its fifth consecutive, and seventh overall, Super League title.

She’s a masterful technician and tactitian, and is unflinching in her pursuit of success. She’s exactly what the USWNT need, and it’s why U.S. Soccer was willing to wait for Hayes.

The USWNT are four-time World Cup champions and have long been the game’s gold standard. But the rest of the world has caught up, and the Americans looked old, sluggish and befuddled in the last two major international tournaments. They were bronze medalists at the Tokyo Olympics and their round-of-16 exit at last summer’s World Cup was their earliest exit ever at a World Cup or Olympics.

They need both a new system and new energy, and Hayes is already giving them a healthy dose of both with her roster choices.

While most of the names on the 23-player roster are familiar — 19 were on the team that beat Canada on penalties last month to win the SheBelieves Cup and another is Rose Lavelle — Hayes made a move that Dunn, and USWNT fans, have been clamoring for, for years.

Dunn is the most versatile player the USWNT has, able to play anywhere on the field. She began her career as a forward and played that position during part of the 2017 season, which she spent playing for Hayes at Chelsea. But former USWNT coaches Jill Ellis and Vlatko Andonovski both played Dunn at left back, wanting to take advantage of her speed and field vision.

How, exactly, Hayes plans to use Dunn remains to be seen. The USWNT has an abundance of talent at forward, with Sophia Smith, the NWSL’s scoring leader; Jaedyn Shaw; Trinity Rodman; Mallory Swanson; Catarina Macario and Alex Morgan also on the roster. But the fact Hayes doesn’t feel bound to long-established roles bodes well for the USWNT.

Hayes also listed Emily Sonnett as a defender. She’s played defensive midfield, and done it quite well, for the USWNT since last summer.

Lily Yohannes, who at 16 is the youngest player to start a Champions League match, got another call-up. She was with the USWNT for SheBelieves Cup but didn’t play.

Besides Williams, the other glaring omission is veteran goalkeeper Alyssa Naeher. But it’s simply a precautionary measure, with Naeher missing the Chicago Red Stars’ game last weekend with a thigh injury.

Hayes also invited midfielder Croix Bethune, who is tied with Smith for the NWSL assists lead (six) in her rookie season, to train with the team in a sign she could be in the mix for Paris. Midfielder Olivia Moultrie and defender Kate Wiesner also will train with the USWNT but not play in the friendlies.

Emma Hayes' full USWNT roster for South Korea friendlies

GOALKEEPERS: Jane Campbell (Houston Dash), Aubrey Kingsbury (Washington Spirit), Casey Murphy (North Carolina Courage)

DEFENDERS: Tierna Davidson (NJ/NY Gotham FC), Emily Fox (Arsenal FC, ENG), Naomi Girma (San Diego Wave FC), Casey Krueger (Washington Spirit), Jenna Nighswonger (NJ/NY Gotham FC), Emily Sonnett (NJ/NY Gotham FC), Sam Staab (Chicago Red Stars)

MIDFIELDERS (6): Korbin Albert (Paris Saint-Germain, FRA), Sam Coffey (Portland Thorns FC), Hal Hershfelt (Washington Spirit), Lindsey Horan (Olympique Lyon, FRA), Rose Lavelle (NJ/NY Gotham FC), Lily Yohannes (Ajax, NED)

FORWARDS: Crystal Dunn (NJ/NY Gotham FC), Catarina Macario (Chelsea FC, ENG), Alex Morgan (San Diego Wave FC), Trinity Rodman (Washington Spirit), Jaedyn Shaw (San Diego Wave FC), Sophia Smith (Portland Thorns FC), Mallory Swanson (Chicago Red Stars)