The 34-year-old called on all his experience in the middle to steer Essex to their second Specsavers County Championship trophy in three seasons, just as title rivals Somerset were scenting an incredible victory at Taunton.
The former England captain scored 53 and 30 not out to claim the draw which secured Essex’s eighth Championship crown and deprived Somerset of their first.
“This keeps you young,” Cook said after adding another Championship winner’s medal to the knighthood that he received earlier this year.
“You’ve got the 19-20 year-olds who put music on the iPod you’ve never heard of and all that kind of stuff.
“I’m not actually that old, but I’ve got a few miles in the legs on a cricket field. I feel like an old man trying to run between the wickets!
“I’ve had a few texts this week saying ‘if you win the league, is that it?’ But I’ve promised Tendo (Essex captain Ryan Ten Doeschate) I’ll play for another year at least.”
Cook’s half-century, his seventh of the summer to add to his one hundred, was crucial as Somerset’s spinners bowled Essex out for 141 – 62 behind on first innings.
England spinner Jack Leach took five wickets and threatened again after Somerset forfeited their second innings and had an hour to bowl out Essex.
Cook stood firm again, however, as Essex finished on 45 for one to add the County Championship title to the Vitality Blast crown they had won only five days earlier.
“I was nervous all week, there’s always going to be little twists and turns,” Cook said. “You don’t bat on a wicket like that and just cruise, you need a little bit of luck on those wickets.
“I have played in sub-continent conditions quite a lot, and I suppose that’s where my experience comes from with a unique method.
“This is so special. All that stuff (knighthood) is great, but it’s about the memories you create with this group of guys. There is a lot of home-grown Essex players and that’s great for our success.
“Obviously we don’t want to look too far ahead, but next year is the same group of players and it could be quite special.”
The title decider did mark the end of one former England batsman’s career as Marcus Trescothick bowed out of the game.
Trescothick announced in June that he would retire at the end of the season and bring down the curtain on a first-class career that began in 1993.
The 43-year-old received a huge ovation as he came on to the field as a substitute for the final few minutes, with Cook saying: “He was out there sledging me!
“He said ‘This will be a story if I catch you right at the end’. Luckily Dominic Bess bowled me one on leg-stump, which I could clip and get away.
“But what a career ‘Tres’ has had. To play for 27 years is extraordinary.”
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