AFTER A SERIES OF BLOWOUT WINS over the past three months, the United States women’s national team passed a much sterner test on Thursday night in Tampa, beating England 1-0.

While the Lionesses asserted themselves early and managed to drag the U.S. into the locker room in a scoreless tie, the Americans took control in the second stanza and rode a 72nd-minute strike from Crystal Dunn to the win. Here are three thoughts on the match.

DIFFERENCE-MAKING SUBSTITUTION

In the 64th minute of play, while England still held the Americans scoreless, England made its first substitution of the night removing Alex Greenwood from the game. However, as she ran off the field, several English players encouraged her to stop running and take her time exiting the match. The English appeared tired and looked to want an extra minute of rest before continuing on with the game.

Just three minutes later, American head coach Jill Ellis inserted Crystal Dunn into the match, surely the last player England wanted to see with their tired legs. Dunn’s hard-charging style made an immediate difference.

Five minutes into her appearance, the 2015 NWSL Golden Boot winner found a pocket of space on the left side of the field, turned a defender and launched a thunderbolt into the upper corner of the net for the game-winning goal.

A masterstroke from Ellis, the substitution changed the game and brought home three points for the U.S.

ANOTHER CHANCE FOR THE YOUNGSTERS

Ellis took Thursday’s match as another opportunity to bleed her youngsters into the lineup, giving 17-year-old Mallory Pugh her fourth start in a row and giving 22-year-old center back Emily Sonnett a start against top-level competition.

Pugh, who impressed many in the Olympic qualifiers last month, continued her excellent run of form, making several strong runs down the left flank and nearly breaking down the English defense on repeated occasions.

Mallory Pugh shows just how fast she is: SheBelieves Cup #womensfootball #SheBelievesCup #Lionesses #USWNT #USAvENG pic.twitter.com/9l6it7WphW

— WomensSoccerUnited (@WSUasa) March 4, 2016

Sonnett also rewarded her manager’s faith, putting in a solid effort in the back. While Sonnett struggled in her first start against Brazil last October, she did not commit any gaffes on Thursday and cleaned up a number of messes when the American backline did break down.

Sonnett notably beat out veteran Whitney Engen for the third center back slot on the Olympic qualifying roster last month. Despite the fact that Ellis did recall Engen for this tournament, Sonnett seems to have further solidified her spot as the first-choice backup with her performance against England.

LOOKING AHEAD

As the Americans move forward in the SheBelieves Cup, there are still several questions facing the U.S. squad.

Kelley O’Hara made her fourth start in a row on Thursday, especially notable because it also marked the third game in a row that veteran Ali Krieger has started on the bench. Whether that change is temporary, or represents a permanent reordering of the depth chart remains to be seen.

It will also be interesting to see what Ellis does with Dunn moving forward. Will Ellis continue to use Dunn as a super-sub to run at tired defenses, or does Dunn deserve another opportunity in the starting XI? The U.S. has good depth out wide with Tobin Heath and Mallory Pugh as the regular starters, and Dunn does tend to struggle in tight space on the flank early on in games.

One other, more radical, option would be to use Dunn at forward. The pairing of Alex Morgan and Carli Lloyd up top seems to run hot and cold, especially over the past few months when the formation has looked more like a 4-4-2 with Lloyd playing as true forward, rather than the 4-2-3-1 that led the Americans to World Cup glory last summer.

Perhaps dropping Lloyd back into a true midfield position (in place of Lindsey Horan) and adding Dunn up top, or replacing Morgan with Dunn as the lone striker will help the Americans get their offense back into top gear. With two more friendlies against top-notch competition in the next five days, it’s certainly worth a look.

The U.S. next plays No. 3-ranked France on Sunday (3pm ET, ESPN3).

John D. Halloran is an American Soccer Now columnist. Follow him on Twitter.