Undera had a comfortable win over Central Park St Brendans after bowling the Tigers out for 69.
Tyler Maher (15) and Hassan Ali Mohamadi (10) were the only CPSTB players to reach double digits, as all seven Lions bowlers picked up at least one scalp.
Joel Bunce, Travis Guppy and Xavier Moon led the way with two each.
Undera made a rocky start to the chase, losing 3-6 early, but first Russell Sherriff (21 from 11) and then Travis Guppy (31 not out from 22) went on the attack to see the Lions home.
The Lions are looking comfortable at the top of the ladder, a total of 12 competition points ahead of their nearest rival.
The side will host Mooroopna next weekend.
Whitelock E-grade shield
Kyabram’s E-grade side looked set for a huge win when its opening batters, Ethan Hart and Dylan Lopez, both contributed half-centuries to steer their side to 116.
After their retirements, Hart for 55 and Lopez for 50, Mooroopna picked up six quick wickets but a fighting unbeaten 18 by Kristian Chambers enabled his team to claim a four-wicket win and hold third spot on the ladder with three games remaining before the finals.