Scotland: Scott Brown says 'no going back' on retirement call
Celtic captain Scott Brown believes he had to be selfish when deciding to retire from international football.
Brown quit the Scotland fold last week having reached the 50 cap mark, to focus all his attention on his club.
However, the 31-year-old says he was worried about disappointing national coach Gordon Strachan, who first took him to Parkhead from Hibernian.
"I've been playing international football for 11 years with no break at all, season over season," said Brown.
"It's a sad day for myself. I really enjoyed playing for Scotland and I think the biggest thing for me was letting the gaffer down.
"He brought me to Celtic and he means so much to me. We spoke and he was wonderful, to be perfectly honest."
'I think it's good timing for everyone'
Brown responded firmly to those who have criticised the timing of his decision, with the 2018 World Cup qualifiers beginning in Malta on Sunday, 4 September.
"Well, I don't want to pull out halfway through a campaign, do I?" he told BBC Scotland. "Once my mind's set, that's it. For me there's no going back.
"I'm quite stubborn that way and I think it's good timing for pretty much everyone.
"I've done 11 hard seasons going away on international breaks, not seeing family, not having the chill-out time.
"So, I think it's a good time for me to call it a day."
Speaking at Monday's squad announcement, Strachan admitted the national team were "weaker" without Brown, but did not name his successor as captain.
The Scotland boss confirmed he would speak to West Bromwich Albion midfielder Darren Fletcher, who wore the armband in summer friendlies against Italy and France, but Hull City midfielder Robert Snodgrass has also "thrown his name into the hat".