The Blue Devils faced the challenge this fall of replacing their top scorer. Now they have to replace their top two.

Duke will begin the process of finding its offensive identity without Zach Mathers and Jeremy Ebobisse Tuesday at 7 p.m. at Koskinen Stadium in its first preseason scrimmage against No. 10 Georgetown. Mathers graduated in May, so the Blue Devils knew they would have to replace him, but they recently also found out that they would be without Ebobisse, who withdrew from Duke after two years to turn pro. 

After opening preseason practice last week, the Blue Devils also face uncertainty in net with the departure of goalkeeper Mitch Kupstas. Despite the number of holes in its lineup, Duke added 10 freshmen, including two Top Drawer Soccer 150 players, and two graduate student goalkeepers this offseason and still hopes to make its first NCAA tournament since 2011. The Blue Devils open the regular season Aug. 26 against San Diego. 

“We’re very excited about our potential because we have some really fantastic returning players with a lot of experience," Duke head coach John Kerr told "We have a lot of guys pushing for places early on and we’re just trying to find the right combinations at this point."

Freshman midfielder Suniel Veerakone and freshman forward Colby Agu highlight Kerr's newcomers. Veerakone was ranked as the No. 41 player in the Class of 2016 by Top Drawer Soccer and hails from Caledonia, Mich. A Cary, N.C., native, Agu is very familiar with the Triangle area after playing with the Capital Area Soccer League Railhawks Academy. He also played with the U.S. U19 team this summer.

With a Blue Devil attack that ranked in the middle of the pack of nearly every offensive category among ACC teams last season, Agu, senior Brody Huitema and junior Brian White will headline Duke's attack. Agu was the 110th-ranked player in the class. 

“Colby Agu is a stylish player who can create goal scoring opportunities for himself and provide them for others," Kerr said. "He is very creative and he is dangerous on set pieces."

A key position battle to watch during the Blue Devils' pair of preseason matchups—Duke will host No. 3 Clemson Friday—will be the fight for the starting goalie spot. 

Junior Joe Ohaus started 13 games as a freshman in 2014, allowing 2.00 goals per game, but will be challenged by a trio of newcomers—graduate transfers Ben Hummel and Robert Moewes and freshman Austin Verissimo. Hummel and Moewes—who came to Duke from Princeton and Binghamton, respectively—could bring a level of experience to one of the ACC's worst defenses in 2015.

Duke surrendered 1.6 goals per game last season and Blue Devil goalkeepers ranked second-to-last in the ACC saves per game—stopping just 2.6 shots per contest. The Duke defense should be bolstered this season by the return of juniors Kevon Black and Markus Fjortoft.

The Hoyas are coming off a Round of 16 appearance in the NCAA tournament but, like the Blue Devils, will have to replace several key pieces in 2016. Georgetown was the tournament's No. 3 overall seed, went undefeated in Big East conference play in 2015 and saw six former players sign contracts with MLS teams after the season. The Hoya defense stood out last year, holding opponents to 0.8 goals per contest.

After watching Duke's newcomers face Georgetown, Kerr and his staff will continue evaluating their unit ahead of Friday's contest against the Tigers.