Matt Prior believes the lifestyle changes he is undertaking off the pitch can make him a better player on it.

The Sussex wicketkeeper-batsmen scored his third hundred of the season yesterday as the county and Lancashire slugged it out in their top-of-the table Championship match at Hove.

Afterwards, the 24-year-old revealed how he has given up alcohol, monitors his diet more carefully and is using a sports psychologist to give him every possible chance of maximising his talent.

His 112 helped Sussex make 438, their highest total of the season at the County Ground. Lancashire will resume today on 246-4 after the peerless Stuart Law completed the 75th hundred of his career just before the close.

Prior is desperate to play for England again and the fact that chairman of selectors David Graveney watched him lodge his 14th first class hundred will not have done his chances any harm.

Being left out of the national development squad in May prompted Prior to examine every aspect of his game - and he is thrilled that the sacrifices he has made in the last few weeks are starting to pay dividends.

He said: "After the England thing I asked myself How much do I really want it?' so I made some lifestyle changes so I can be harder on myself and more disciplined.

"I haven't touched a drop of alcohol for six weeks. I've never been a huge drinker but I have made that choice.

"And I've been working with Michael Caulfield, a sports psychologist, on improving my mental toughness. It's about knowing where I want to get to in my career and how I'm going to get there.

"I've got notes all over my flat to remind me of certain things.

On the front door it says Is this going to help you get where you want to be?' So if someone calls asking if I want to go for a few beers I see that and think again. Nowadays, I'll stay in."

Prior is religiously going to the gym after each day's play - even if he has spent it in the field - and is watching his diet. Things like chocolate and biscuits are off the menu.

He added: "Doing all the right things off the field doesn't guarantee you are going to get a hundred or keep wicket well every time but when it happens it is enormously satisfying and quite exciting in a way. At the moment I feel I am playing as well as I have for 18 months.

"But if it doesn't happen for me I know it won't be because I haven't given myself the best opportunity to succeed."

Not so long ago Prior would have become frustrated by the docile nature of this Hove pitch.

But after grafting his way to a half-century on the first day he acclerated during the morning, his second 50 coming off just 66 balls.

He hit Tom Smith out of the attack with four boundaries in an over as he helped Robin Martin-Jenkins extend their sixth wicket stand to 184.

But Prior is still fallible and when Dominic Cork returned to the attack after having his dislocated finger patched up, he immediately peppered him with several short balls and Prior eventually mis-timed a back foot upper-cut, having faced 159 balls and hit 17 fours.

He said: "It was a different game when Corky was trying to hit me on the head but I enjoy that sort of challenge. The one ball when I came out of my zone I got out and I was so annoyed with myself for doing that.

"But I will learn from it. I would have taken 112 when I went in and we were 161-5. It was nice to play that sort of innings in front of a good crowd, including the chairman of selectors, in a high-profile match."

The rest of the lower order took the lead from Prior and Martin-Jenkins, who was leg before to slow left-armer Gary Keedy after they had lifted the tempo of the innings by adding 53 in the first 45 minutes.

Luke Wright and Yasir Arafat added to Lancashire's frustrations by putting on 62 and Wright had just enough time to score a composed halfcentury, his third of the season, before the persevering Cork wrapped up the innings with his fourth wicket.

Lancashire soon ran in to trouble in the form of Jason Lewry who took the first three wickets.

Mark Chilton pushed thesixth ball of the innings to short leg, Mal Loye was defeated by late inswing and Iain Sutcliffe caught behind immediately after the leftarmer switched to the Cromwell Road End.

Law and Nathan Astle counter-attacked either side of tea but Chris Adams made another successful bowling change when Yasir Arafat uprooted the Kiwi's middle and leg stumps as he played across the line.

But Lancashire were emboldened by an attacking half-century from wicketkeeper Gareth Cross in the final hour and Sussex's chances of forcing the win they need were not improved when Mushtaq Ahmed limped out of the attack halfway through his 19th over with a groin twinge.

They need to remove Law, who has so far hit 14 fours and a six, as soon as possible this morning to give themselves a chance of forcing victory.

Liverpool Victoria County Championship division one: Canterbury: Kent 285 v Hampshire 171-2 (J P Crawley 113 no). Riverside: Durham 195 (P Mustard 81, C E Shreck 6-67) & 157 (C E Shreck 4- 64) v Nottinghamshire 139 (G Onions 4- 37) & 17-1.

Division Two: Southend: Essex 252 (R C Irani 80, A R Caddick 5-82) & 208-4 v Somerset 133 (A J Tudor 5-67). Colwyn Bay: Worcestershire 460 (D K H Mitchell 134 no) v Glamorgan 329-9 (A G Wharf86). Cheltenham College: Gloucestershire 282 (C W Henderson 5- 76) v Leicestershire 406-5 (J K Maunders 178 no, P A Nixon 103). The Brit Oval: Northamptonshire 347 (B M Shafayat 91) v Surrey 417-2 (M R Ramprakash 174 no, S A Newman 143).