Julie Ertz seemingly always finds herself in the middle of things. (Jack Gruber-USA TODAY Network)

By Michael Lewis

FrontRowSoccer.com Editor

They’re a No. 6 to the rest of the world, but they are No. 1 in my book.

I doesn’t matter whether they are called defensive or holding midfielders, they all mean the same to many teams.

You have an organizer in the middle of the pitch, someone who can play both sides of the ball and help a side transition from defense to attack with relative ease, and you’ve got half the battle.

The U.S. women’s national team has one in Julie Ertz.

Ertz made an impact and then some on both sides of the ball in the Americans’ 6-1 Group B win over New Zealand in the Tokyo Olympics Saturday. Besides her zest to win every ball that comes her way, the midfielder also set up two goals. Ertz, who hadn’t played a match until Wednesday since the beginning of May due to an MCL injury, went the distance.

If you don’t realize how vital defensive mids are to teams, both club and country, here’s a super quick tutorial.

This writer was schooled about the importance of a transition player since I began covering soccer back in the stone-age days of 1975.

Rochester Lancers midfielder Francisco Escos, whom team owner Charlie Schiano dubbed the “assassin,” was the first defensive standout I remember. Escos wasn’t afraid to get a yellow card because he wasn’t afraid of playing the ball and if necessary, on occasion, the man.

He was followed by Renato Cila and Val Tuksa, a demon when it came time to dispossess the opposition.

Internationally, teams with superior defensive midfielders have taken the final victory lap of a competition. Do the names Dunga, Patrick Vieira and Lothar Matthaeus ring a bell? Well, they helped anchor their respective national sides to World Cup championships. Dunga did his damage with Brazil at USA ’94, while Vieira, who guided New York City FC to success during his tenure, was a key to Arsenal’s success back in the way. Matthaeus, a member of the 2000 MetroStars, played a key role in guiding Germany to the 1990 World Cup crown.

More recently, N’Golo Kanté, who helped Chelsea to the UEFA Champions League crown and a member of the French national team that captured the 1998 World Cup.

Chris Armas emerged as the best defensive midfielder during Major League Soccer’s early years. He accrued 66 international appearances, but never appeared in the World Cup or Olympics due to several untimely knee injuries. Former Grenada international Shalrie Joseph, a St. John’s University legend, helped the New England Revolution to three consecutive MLS Cups.

Other players have emerged as central midfielders, including Austin FC’s Alex Ring, who earned his MLS reputation with NYCFC. Today, former Red Bulls midfielder Tyler Adams is considered the best USMNT player to man that role.

The USWNT has a pretty damn good history topflight defensive mids. When Epstein-Barr Syndrome hit Michelle Akers, she switched to midfield and essentially defined that position for the women with her physical and never-say-die play. Shannon Boxx and Ertz most recently have followed her tradition.

Ertz gave the USA midfield backbone Saturday, doing a lot of the dirty work. It paid off.

Interestingly, head coach Vlatko Andonovski let the 29-year-old Ertz play the entire 90 minutes. Apparently, he wanted to stretch out her minutes after performing in a half a match in the Sweden opener Wednesday.

The USWNT will need all hands, and feet for that matter, on deck for Tuesday’s confrontation with Australia, which will determine which team takes second in Group G.

Ertz will have certainly will have her work cut out for herself, trying to win the ball from the Matildas midfielders and helping to close down the passing lanes to the fabulous Sam Kerr.

If she accomplishes both, we again will be reminded that you don’t always have to score goals to take center stage and how valuable she is to the USWNT.

Front Row Soccer editor Michael Lewis has covered 13 World Cups (eight men, five women), seven Olympics and 25 MLS Cups. He has written about New York City FC, New York Cosmos, the New York Red Bulls and both U.S. national teams for Newsday and has penned a soccer history column for the Guardian.com. Lewis, who has been honored by the Press Club of Long Island and National Soccer Coaches Association of America, is the former editor of BigAppleSoccer.com. He has written seven books about the beautiful game and has published ALIVE AND KICKING The incredible but true story of the Rochester Lancers. It is available at Amazon.com.