The U.S. women’s national team will be without defenders Becky Sauerbrunn and Julie Johnston as well as midfielder Morgan Brian due to injury on Saturday for the team’s firsts match of 2016, against Ireland in San Diego, Calif.

Sauerbrunn and Johnston are both back to full training, per a U.S. Soccer representative. Sauerbrunn has been dealing with a knee injury in camp and Johnston had a groin issue, but both are being held out of Saturday’s games as precautionary measures. Brian recently picked picked up a knee injury during training. They are expected to be ready for Olympic qualifying, which begins on Feb. 10.

U.S. coach Jill Ellis is short on center backs with Sauerbrunn and Johnston out Saturday. Christie Rampone is also out several weeks after having knee surgery in December. That leaves Whitney Engen and recent No. 1 overall NWSL Draft pick Emily Sonnett as the lone remaining center backs on the roster for Saturday. Sonnett and Engen look like likely starters for Saturday, but don’t be surprised if fullback Ali Krieger gets a look as a center back at some point on Saturday against a relatively weak Ireland team. With the U.S. light on numbers at center back, Krieger has spent some time training in the position during this January camp.

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Withholding clear starters Sauerbrunn and Johnston from the lineup will allow U.S. coach Jill Ellis to get an extensive look at Sonnett and Engen, a pair of center backs who have seen limited game action who, along with Rampone, are likely fighting for one spot on the 18-player Olympic roster.

Sauerbrunn was recently appointed co-captain of the U.S. women along with midfielder Carli Lloyd, who was recently named the 2015 FIFA Women’s World Player of the Year. Both Sauerbrunn and Lloyd were essential to the United States’ 2015 World Cup triumph.

Saturday’s match is the first of the calendar year for the U.S. women, who ended their 2015 campaign with a shocking but, as Abby Wambach called it, fitting loss to China at the Superdome in New Orleans, La. The loss snapped a 104-game, 11-year home unbeaten streak for the United States.

So the U.S. women start anew on Saturday, beginning another challenging calendar year in which they are faced with building for the future while competing in the present. It’s hardly a groundbreaking concept, but it is one of particular scrutiny for the No. 1 team in the world, fresh off a World Cup title.

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Winning a fourth consecutive Olympic gold medal in 2016 is the goal. The Americans will likely be favorites heading into the tournament, a competition whose setup — six games in 16 days for the finalists with only an 18-player roster — lends to the United States’ strengths in depth and fitness.

Ireland should serve as a soft warm-up, with the U.S. having won all 11 matchups by a combined score of 40-1, including a 3-0 victory last May ahead of the World Cup.

Olympic qualifying begins in Frisco, Texas on Feb. 10 with group games against Puerto Rico, Mexico and Costa Rica. The top two teams from the group advance to the semifinals, where winners of those semifinals will book tickets to the Olympics. The U.S. and Canada are heavy favorites for the two Olympic berths.

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