They were the first and second-place teams in a tough Mid-Suburban West softball conference this season.
Now Conant and Barrington, who both have 25 wins, are the only two Cook County area teams remaining in the state tournament.
The Mid-Suburban champion Cougars, coached by 14-year veteran CathyAnn Smith, head to the Bartlett sectional with the No. 2 seed and a 25-5 record while Barrington coach Perry Peterson, a veteran of 22 seasons, takes the Fillies to the Jacobs sectional with a record of 25-11.
At Bartlett: Enjoying one of their finest seasons in school history, Conant will try to extend it further when they meet No. 3 seed St. Charles East (30-6) in today's 4:30 p.m. sectional.
The Cougars have already won their third MSL title in four years and second regional in three years, belting a school-record 49 home runs along the way.
Leading the way are Rachel O'Malley with 11 homers, followed by DeeDee Durr (10), Sara Neuman (6), Hailey Rothstein (6), Alissa Wachal (6), Dream Aaron (5), Telly Hunter (3), Kim Zaucha (1) and Kali Schumacher (1).
Leadoff batter Elisa Ambrose leads the club with 13 doubles. Freshman Lauren Grzelak has 12 hits and classmate Rachel Falbo has added 8.
Neuman (12-2), Schumacher (8-2) and Kim Zaucha (5-1) have handled pitching duties this spring.
The Cougars are playing in their fourth sectional, with regional titles in 1980, 2002, 2005 and 2012.
St. Charles has won eight regional titles and was a sectional champion in 2004 and last year when it finished as the Class 4A state runner-up.
Saints pitcher Haley Beno, who defeated Elk Grove 5-2 to win the St. Charles East regional title, is 20-4 with a 1.34 ERA. Top hitters for the Saints are Tess Hupe (. 528) and Sarah Collalti (. 568).
St. Charles East defeated Conant in the regional final last season and in 2009.
The winner of this game moves on to Saturday's 11 a.m. championship game where it will meet top-seeded Glenbard North, a 10-4 winner over No. 4 St. Charles North in Tuesday's semifinal.
at Jacobs: Barrington took third place (36-2) in the Class 4A state tournament a year ago and pitcher Keenan Dolezal is back this year with a 24-9 record after compiling a 29-2 mark as a junior.
The junior right-hander, a Loyola recruit, has thrown two shutouts in the postseason, defeating Jacobs 3-0 and Cary-Grove 10-0 at the Cary-Grove regional.
First pitch is scheduled for 4:30 p.m. against Hononegah (28-5) which has won six straight Northern Illinois Conference crowns.
Hononegah blanked Harlem last week 4-0 to win its 10th regional. The Indians won sectional titles in 1989 and 2004.
Hononegah was the top seed when it won the Rockford Guilford regional, defeating No. 2 Rockford Harlem.
Barrington won its eighth sectional crown last season en route to its fourth-place finish.
Hall of Fame Barrington coach Perry Peterson (680 wins) has never played Hononegah in his career (21 years at Barrington and one at St. Viator).
"We look forward to the opportunity that this sectional presents," said Peterson who has guided the Fillies to seven sectional crowns. "We hope to do what we've been working on all season long."
The winner of this game moves on to Saturday's 11 a.m. championship game where it will meet DeKalb, an 8-4 winner over McHenry in Tuesday's semifinal.
DeKalb won the Huntley regional as the top seed.