Gilliam (3-0) struck out 10 and walked four in earning the victory. He pitched out of a jam in the fourth inning with runners on second and third.
The Mustangs (8-3, 1-0) had six hits, but it was Michael Atkinson’s two-out, two-run single in a three-run fifth inning that made the difference.
Kennesaw Mountain will host South Cobb on Friday.
Kell 14, Osborne 0: Kell scored six runs in both the third and fourth innings to run away from the Cardinals.
Austin Guevlo went 2-for-3 with two hits and two RBIs, while Justin Russell went 2-for-4 with two hits, one run and a double and Jared Donald went 2-for-3 with two runs, three RBIs and a double.
Starting pitcher Jake Lecroy earned the win in just two innings, while Marshall Sturdivant and Andrew Mitchell finished on the mound.
Kell (4-5, 2-2) will play at Creekview on Friday.
Harrison 9, Walton 1: Hunter Fortner led the Hoyas, going 3-for-4 with three singles, three RBIs and two runs scored.
Tanner Weeks had two singles and two RBIs, Jayson Cook had two hits and Cole Austin scored four runs despite just one hit.
Andrew Patrick (3-0) allowed four hits against three strikeouts in five innings, while James Williams allowed no hits in the last two frames.
Harrison (6-1) will play at Pebblebrook on Monday.
Pope 5, North Springs 2: Pope trailed 2-0 and was down to its last strike when Josh Lowe hit a game-tying double.
Harrison Siegal, who went 3-for-4 on the night, had doubled in the previous at-bat, also with two outs.
With the score 2-2, Steven Skruck finished the comeback victory with a three-run homer.
Starting pitcher Matt Rowland threw a complete game, allowing just two runs on four hits against three strikeouts.
Siegal pulled the score within one heading into the final frame with a solo homer in the sixth.
Pope (5-5, 4-1 Region 7AAAAA) will host Forsyth Central on Friday.
Kennesaw Mountain 3, Etowah 2: Etowah took a 2-1 lead into halftime on an own-goal, but Edgar Martinez rallied the Mustangs with two more goals in the second half to complete a hat trick for the day.
All three of Martinez’s goals were unassisted, with this third goal coming with 18 minutes left to play.
Kennesaw Mountain (2-5) will play at Sequoyah on Friday.
Walton 162, Lassiter 173: Nick Orell-Jones shot a 1-under 35 to lead the Raiders, followed by a 39 from Garrett Neptune.
Sam Donnelly shot 42 and Will Gosnell 46 to complete the win at Indian Hills Country Club.
The win was Walton’s first match victory of the year.
The Raiders will play in a tournament at Bentwater Golf Club this weekend.
Walton 136, Milton 136: Walton lost a 4-shot lead on the final hole, leaving the Lady Raiders tied with Milton.
Abbey Williams led with a 41, followed by 47 from Autumn Gabe 48 from Lindsay Seagraves.
The Lady Raiders (1-0-1) will play in the Red Elephant Tournament on Saturday at Chattahoochee Country Club in Gainesville.
Harrison 138, Blessed Trinity 143: Hailey Willman led the Lady Hoyas with a 44, followed closely by a 45 from Caroline McLeod and 49 from Jordan Abbott.
Harrison, 2-0 in match play, will play host North Paulding on Tuesday.
Hillgrove 17, McEachern 4: Katie Russell led the Lady Hawks with four goals, followed by three goals and two assists from Morgan Perrone.
Erin Pruitt and Marilyn Primovic each scored two goals, while Olivia Ellis scored one goal and had four assists. Defender Sarah Castleberry forced seven turnovers and had three ground balls and three draw controls.
Hillgrove (4-1-1, 2-0 Area 1AAAAAA) will host Wheeler today.
Marietta 5, Campbell 0: The Blue Devils didn’t drop a set in winning the Region 4AAAAAA match.
Zachary Garrison won 6-1, 6-1 at No. 1, and David Ho 6-3, 6-1 at No. 2, while Marcos Brito recorded a shutout at No. 3.
Jackson Mitchell and Matt Efromov won 6-2, 6-2 at No. 1 doubles, with Neal Majors and Charlie Tripp winning 6-3, 6-4 at No. 2.
Marietta (6-2, 3-1) will step out of region play to host Cass today.
Kennesaw Mountain 3, Harrison 2: The Mustangs swept the singles, while Harrison won both doubles matches.
Matthew Osajima (6-2, 6-0), Justin Thomas (6-3, 6-2) and Mikey Deatrich (6-0, 6-3) won in the singles, while Harrison’s Ben Maryland and Peter Heflin (6-3, 6-1), and Dylan Harvey and Matthew Griffin (6-1, 6-2) won in the doubles.
Kennesaw Mountain (3-3, 2-1 Region 4AAAAAA) will play at McEachern today.
Kennesaw Mountain 4, Harrison 1: A singles sweep sparked the Lady Mustangs on to beat their Due West rival.
Nicole Croxton won 6-0, 6-2 at No. 1, Samantha Armas 6-1, 6-3 at No. 2 and Abby Seabaugh 6-4, 6-3 at No. 3.
Chika Okonkwo and Ivy Evatt added a 6-2, 6-3 win at No. 1 doubles.
Harrison’s Autumn Weakley and Mika Sugai won 6-3, 1-6, 6-4 at No. 2 doubles.
Kennesaw Mountain (5-1, 3-0 Region 4AAAAAA) will host McEachern today.
Kell 5, Forsyth Central 0: Samantha Dearing, Katie Tarbell and Kysia Katsoudas all won in 6-0, 6-0 shutouts.
Dani Carroll and Shelby Nyberg (6-0, 6-0) and Jada Robinson and Meela Patel (6-1, 6-0) won in doubles to complete the team shutout.
Kell (9-2, 6-1 Region 7AAAAA) will host Pope for senior night today.
Marietta 5, Campbell 0: Morgan Haycraft (5-7, 6-2, 12-10), Nicole Hartley (6-2, 6-1), and Heather Bundy (4-6, 6-4, 11-9) won in the singles.
Aya Maghribi and Sydnie Fairman won 6-2, 6-2 in the doubles, followed by a 6-0, 6-4 win by Tessa Weddington and Libby Grant.
Marietta (4-1) will host Cass later today.