Chris Brown opened with a penalty for Warwickshire, following a break by flanker Simon Morris, after two minutes, but two Steve Nutt penalties gave Lancashire the edge before winger Oliver Brennand crossed on an overlap for the opening try to end the first quarter.
Warwickshire replied four minutes later when prop Phil Boulton touched down in support of winger George Dixon, Brown converting to trim the gap to a point, before unconverted treis by No.8 Sebastian Moss and Brennand sent Lancashire into the break with a 23-10 advantage.
Brown pulled back a penalty soon after the restart, only for tries by Nutt - which he converted himself - and winger Nick Royle to cross in the space of four minutes as the home side threatened to run away with things.
The rest of the game, however, belonged to Warwickshire who took charge in the forwards with driving play which brought tries for winger Kurt Johnson and Morris, the second converted by Ben Russell, and set up an anxious last ten minutes for the hosts.
Warwickshire: Lowden (Waterloo); Dixon (Coventry), Hersey (Kenilworth), Russell, Johnson (both Cov); Brown (Ken), Jones (Cov); Greevy (Barkers Butts), Whitehead (Cov), Boulton (Rotherham), Hodge (Cov), Weaver (BB), Simkiss (Broadstreet), G Southwell (Nuneaton), Morris (B'street). Replacements: Croft (Nun, for Brown), Thomas (Nun, for Jones), Dugard (Cov, for Greevy), C Southwell (B'strret, for Whitehead), Cheney (Rugby Lions, for Weaver), Serderavic (Univ of Warwick, for Morris).
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