On a personal level, the period since Lasley returned from Plymouth Argyle for a second spell at the Lanarkshire club in 2006 has provided him with memories and invoked emotions that will last him well into his dotage.
In terms of pure footballing achievement, though, the midfielder, now 34 years old, suspects the greatest high of all lies just 90 tantalising minutes away.
Motherwell, of course, have already booked their place in the qualifying stages of next term's Europa League, the sixth time in seven seasons that they will have represented Scotland in Uefa competition.
Finding themselves at the right end of the Premier League is nothing particularly new either. They finished runners-up to Celtic last term and came third in season 2011/12. There was, too, the small matter of a Scottish Cup final appearance three years ago.
Lasley, however, is of the view the past 10 months have been different to all of that. Theirs has been a success carved out against all odds with a squad that was torn apart by the departure of six first-choice players last summer and a budget that almost certainly amounts to less than half of that enjoyed by their rivals for second place in the SPFL Premiership, Aberdeen.
Motherwell have already triumphed at Pittodrie this season, winning 1-0 thanks to a Lionel Ainsworth goal on Boxing Day. Should they repeat the dose this afternoon and leapfrog their hosts in the final placings, Lasley believes a sublime campaign really will have reached ridiculous levels.
"Qualifying for Europe six years out of seven is incredible for a club of this size and is something we may look back on in future years as a golden period of the club's history," said the club captain, who is poised to begin negotiations on a new contract with his current deal set to expire.
"If we can come second this season, though, I think it probably tops the lot. A number of changes were made within the squad last summer and we have had some serious injuries to contend with.
"If we manage to come second this year, I think it would be better than the cup finals, the high league placings and everything else. If we do it, we'll have won 22 games out of 38 and that's ridiculous for a club like ours."
And, yet, Lasley might not have been present for all this had things worked out a little differently towards the end of 2009. He had been left out of the picture by the then manager, the decidedly eccentric Jim Gannon, to the degree that he spoke at the time about going out to buy carpets on Saturday afternoons rather than play football.
Those were six black months during what has otherwise been a glorious return to Fir Park. Lasley had more or less made up his mind to leave during the January window when, four days before it was scheduled to open, Gannon was relieved of his duties.
"I am glad I toughed it out, but it was getting to the stage where I didn't have much choice about leaving and there were a few of us in that boat," he explained.
"We felt we had done well for the club and were being discarded. It was the way things were being done that was most disappointing.
"I was certainly very close to leaving. Football is often a matter of fine lines, though, and it was at that stage that Craig Brown and Archie Knox took over. I could have been away that week or a couple of weeks later.
"The last three or four years have certainly been the most enjoyable of my career and Craig and Archie kickstarted that.
"Having the chance to captain the team in the Champions League and the Europa League has been beyond my expectations.
"Some real legends of the game have been Motherwell captains over the years and you should cherish carrying that on.
"The cherry on the cake was that my first game as skipper saw me stepping out against Panathinaikos in the Champions League.
"The whole family came to Athens for the return and attended our away game at Levante that year too. Those nights are the most enjoyable memories of my career and will probably always be."
Perhaps the one saddening aspect of this most pleasing season at Motherwell has been in the attendance figures. This may be, as Lasley attests, a memorable epoch, but statistics reveal that fewer people are going through the Fir Park turnstiles than last season.
"We have a hardcore of about 4000 to 4500 fans," said manager Stuart McCall. "We have been as attractive as possible (in playing style) and tried to give value for money, but I think we just have to accept it.
"Brighter people than me will probably have suggestions, but we can only do what we can."