The Lions stalwart led his side to 8-264 at Rosedale Park, Warwick Farm on Saturday, grinding his way to 101 from 268 balls to register his second century in as many matches.

Lambert hit 12 boundaries in more than five hours at the crease, anchoring the innings that saw no other batsman pass 50 runs.

Dean Attard and Russell Wilcoxon scored 34 and 33, respectively, while Wendel Delpechitra and Matthew Harivel chipped in with 29 runs each.

Charles Matthews was the pick of the UNSW bowlers, taking 4-59 off 17 overs, ripping through the Lions top order with the first three scalps of the day.

In second grade, the Lions have a tough assignment ahead of them on Saturday after UNSW declared at 9-371.

In reply, the Lions are 1-21, still 350 runs behind their opponents' first innings total.

The Lions third grade team are also facing defeat after being rolled for 171. UNSW are in the box seat after finishing day one at 2-86.

It's all smiles in the fourth grade camp after two of their batsmen celebrated centuries on the weekend.

Daniel Marshall (112) and Shaun Bridges (103 not out) combined for a 165-run seventh wicket partnership, steering the Lions to 7-352 at stumps. Fifth grade scored 164 and had UNSW at 1-57 at the close of play.

The Lions first grade team will play a Twenty20 match on Sunday against Mosman at Rawson Park, Mosman from 3pm.