Despite the dank, damp September that has arrived spin could secure Lancashire a vital victory in the Championship race. A surface that started green began to offer significant help to the spinners as the home side thought it would when they selected Simon Kerrigan alongside Gary Keedy. Hampshire, who closed on 229 for 5, will have to bat last and remain a long way from first-innings parity.

And Lancashire also struck lucky with the weather as showers skirted Liverpool before the afternoon brightened. However, they found Hampshire hard work to crack initially - they are fighting for their Division One life - as Jimmy Adams and Liam Dawson added 103 for the first wicket. Then, though, the inroads arrived as four wickets fell for 40 either side of tea but Hampshire battled hard to stay in the contest. Worcestershire's problems against Sussex mean they still have a glimmer of hope.

This a pitch where persistence is required because wickets can fall in clusters. For 37 overs Lancashire were frustrated as Adams and Dawson suggested Hampshire were setting a platform to challenge the hosts' 388. Dawson reached a hard-working fifty from 107 deliveries before trying to cut Kerrigan ("one that didn't turn" he said with a smile) and losing his off stump. Lancashire earned another breakthrough on the stroke of tea when Michael Carberry was bowled round his legs by one that spun from Keedy. It was the last ball of an additional over because Lancashire's over-rate was good and they bowled an extra eight for the day.

Watching the two left-arm spinners, Keedy and Kerrigan, in tandem - a period which lasted 48 overs - gave a glimpse at the past, present and future of Lancashire's spin bowling. Keedy, the senior pro, is being widely linked with a move to Warwickshire next season because they are willing to offer him a longer contract. Lancashire, for their part, are over-loaded with left-arm spinners - they also have Stephen Parry - and don't want to make Kerrigan, who is playing just his third Championship game of the season, uncomfortable about his future by Keedy blocking his development. On the evidence of this match Kerrigan can develop into a fine replacement. The England selectors have taken note, too, with an England Lions call-up.

For now, Kerrigan is enjoying the partnership with Keedy which, he admitted, took time to settle. "We did it a little bit last year when Keeds came back from injury but we didn't quite click because we were trying to outdo each other," he said. "We had a talk about and said if he could just build pressure then they feel it and there's no outlet."

After tea the wickets came again. Adams, who scored 207 against Somerset last week, had reached fifty from 132 balls but didn't go much further when he was well caught at slip by Paul Horton who dived almost behind the keeper to hold a fine edge. That catch, however, was nothing in comparison to the one Horton took next to remove James Vince as he dived low to his left to claim an outstanding grab.

Neil McKenzie and Sean Ervine withstood the attack for 18 overs but the scoreboard didn't move very quickly as the spinners maintained pressure. Keedy, from the River End, made the breakthrough when McKenzie lunged forward and edged to Gareth Cross. Another wicket before the close would have left Lancashire well placed for a handsome lead - and that prospect is still there for the morning - but Ervine and Michael Bates played well to see out the day.

Ervine used his long reach to try and get to the pitch, twice lofting Kerrigan over the leg side, but was given a life on 47 when Cross couldn't gather an edge. He reached his fifty from 79 balls and he remains Hampshire's best chance of closing the gap. It was exclusively spin throughout the last session with only three overs of Steven Croft breaking the monopoly of the left-armers. "We knew the pitch had been used and would spin. Now it's down to me and Keeds to turn it on," Kerrigan said. "We just need to be patient."

Earlier, Lancashire had fallen 12 runs short of maximum batting points but to post 388 from being 125 for 5 on the first afternoon was a wonderful performance. Glen Chapple and Kyle Hogg carried their eighth wicket stand to 116 - a new Lancashire record against Hampshire - before Hogg was trapped lbw by Dimitri Mascarenhas.

Chapple's innings was a boundary-studded affair, but in the 90s he moved into single mode and kept losing the strike to Kerrigan. Then Chapple tried to reach three figures for the first time since 2004 with a lofted shot down the ground but could only pick out deep mid-on. Keedy and Kerrigan added another 19 as the 400-mark loomed and although they fell short their most important role for the day was still to come.