The last remaining women in training at the Army’s grueling Ranger School has been held back from graduating Friday, but could still become the third female soldier to complete the course later this fall, Army officials said Tuesday.

The woman was “recycled,” or held back, to attempt the third and final phase of the school for a second time at Eglin Air Force Base in Florida. If she completes it, she would join Capt. Kristen Griest, 26, and 1st Lt. Shaye Haver, 25, as the first female graduates of the school, considered one of the most difficult in the military.

Griest, Haver and the third woman still in training were among 19 women who attempted Ranger School beginning April 20 as the Army opened it to women as part of ongoing research to determine how women can be better integrated into the military. Sixteen women have been dropped from the course, while Griest and Haver made history and graduated Aug. 21.

That leaves the remaining woman, who has ground it out at Ranger School for 148 days and counting as of Tuesday. A major and graduate of the U.S. Military Academy at West Point, N.Y., she joined Griest and Haver as the only women to advance to Ranger School’s second phase in the mountains of northern Georgia, but fell behind them when they completed it on their first try.

The remaining female soldier advanced to the third phase of Ranger School in the swamps of western Florida last month, but was recycled this week along with 20 male soldiers, Army officials said Tuesday. The school will graduate 140 male soldiers in a ceremony at Fort Benning, Ga., on Friday.

The success of the women at Ranger School has put additional pressure on the military to open all jobs to female service members. The Army announced Sept. 2 that it would remove all restrictions on women attending Ranger School in the future. Army Secretary John McHugh said in a statement that the service must ensure that the opportunity afforded to Griest and Haver is available to “all soldiers who are qualified and capable,” and that the Army is continuing to examine how to select, train and retain its best soldiers.

Gen. Mark A. Milley, the service’s top officer, added in the same statement that combat readiness remains the Army’s top priority.

“Giving every qualified soldier the opportunity to attend the Ranger Course, the Army’s premier small unit leadership school, ensures we are maintaining our combat readiness today, tomorrow and for future generations,” Milley said.