Though 37 years of age, Kumar Sangakkara has recently been in the form of his life. In 2014, he played Tests against Pakistan, England, South Africa, Bangladesh and New Zealand to hit 1438 runs at an average of 71.90. In the 12 months, he hit more international runs, across formats, than have ever been struck in a calendar year. In March, he became the first batsman to hit four ODI centuries on the trot, at the World Cup. And as his catching in the Pakistan series have shown, he remains as sharp as anyone in the Sri Lanka side.

So why is he quitting now? Sangakkara said it was his father, who has been a well of advice to him throughout his career, who first suggested it may be time to step away.

"My father, when I was at home with him a couple of years ago in Kandy, asked me: 'Don't you think it's time you started thinking about retirement?' I got a shock. I thought, 'What are you trying to tell me? That I'm not good enough?' But then speaking to my mind, it actually made some sense. It was back in 2012 or 2013 when he asked me that, and it struck home. I thought, 'Maybe it was time I paid attention to what's happening.'

"Then when I had my back injury against India in October last year and I came back, it just kind of felt right. The voice in my head was there from maybe that July South Africa series when Mahela decided to retire. It was strange because I had decided before him to start writing a letter, when he called me and told me that he was retiring. I said, 'Okay, that's fine. We can't have two people going at the same time.'

"But I spoke to my father, and I spoke to my family. My wife told me that playing for Sri Lanka would be great for us as a family, because that meant I'd be spending a year at home. But even she felt that it was time for me to call it a day. When I heard that, I realised it was absolutely the right decision for me to make."

Had Sangakkara stayed on, he would have had several Test milestones on his horizon. He is fifth on the Test run-scorers list now, but on form, he might have conceivably finished with close to 14000 runs. He is also two short of 40 Test hundreds, though, in the five potential innings that remain, there remains a chance he could hit one more double-century to match Don Bradman's tally of 12.

"I've been told if I play another year or two years, I could score another 1000 runs. I might be the second highest run scorer, or I might be able to break the Don's double-century record," Sangakkara said. "But if you really think about it, if that's the only reason you want to prolong your career, then it is really time to say, 'Thank you very much.'

"I've always prided myself on performing well for the side as an individual, but at the end of the day I want to be able to look my teammates in the eye and say I went out there because I really wanted to do well for the side, and it was nothing to do with individual records. I can do that right now. Extending my career for a year doesn't make a lot of sense. Two to three years maybe, but then I'll be 40, which is too long.

"I still remember what Muttiah Muralitharan told me when he was retiring. When the selectors sat with him, and he said he'll be playing only one Test in the India series, but he still needed eight wickets to reach his 800 wickets mark. We told him to play more matches and go for that 800 wickets. He said, 'If I can't take eight wickets in one match, there's no point. If I take eight, we're going to win that match.' I'll play my last two Tests the way I get them. I consider myself very fortunate to play for my country for 15 years."

Sangakkara said he took particular satisfaction from the runs he made overseas. He averages over 60 in Australia, New Zealand and the UAE, and more than 40 in England, with Test hundreds in all nations apart from the West Indies, where he's played only seven innings.

"In Sri Lanka, we take pride in winning away from home and scoring runs away from home in conditions that are tough. So I've enjoyed every hundred I've scored, but the ones away from home are special.

"The third Test against South Africa in Centurion in my second Test series, I was batting on 98 - and I hope I don't get in trouble with the ICC - but I got a pretty bad decision. I was on 98 batting with Ruchira Perera at the other end. That was a really important innings for me because I played against a really tough pace attack - quick wickets - and that was probably the first time I thought I can become a Test player. My first Test series in Sri Lanka, I had had a terrible time.

"Then scoring a century against Australia was special. I had a grade two hamstring injury, and I managed to get back in 16 days and score a century in Hobart, in a losing cause unfortunately. Everyone wants to score runs against Australia, because you consider them the toughest side.

"Then there was the hundred in England at the Rose Bowl, which was very, very satisfying. I've found England very hard to bat in. I've watched Marvan score runs there, Dilshan, Mahela, Aravinda, Sanath all got runs. I watched all these players, and when I found it difficult, I had to come to terms not only with conditions, but also my own expectations."

Sangakkara's major disappointments were no surprise. He was captain when Sri Lanka were runners up in the 2009 World T20 and the 2011 World Cup. He also played in the 2007 World Cup final and 2012 World T20 final, both of which Sri Lanka lost. He is part of the reigning World T20 champion team however, having hit an unbeaten fifty in the final of that tournament, in Dhaka.

"I think there have been about four sad days - all the World Cup finals where we didn't cross the line. You wish you'd been on the other side, but you can't help it. Imagine if I'd been able to walk away with two 50-over World Cup wins and three T20-over World Cup wins. That would be amazing.

"But I've been a part of some very special teams. I've watched Aravinda de Silva, Arjuna Ranatunga, Sanath Jayasuriya and Marvan Atapattu bat. I've watched Murali and Chaminda Vaas bowl amazing spells - Vaasy especially on the dirt tracks in Sri Lanka. Rangana Herath - who would have thought, looking at Rangana, that he'd have the record he has? It's unbelievable. I've been part of some special teams and some special wins. There are sad days, but a lot of better days that I remember."