But rather than his personal milestone, the Manchester United midfielder is focused on qualification for Euro 2012.
Scotland have not qualified for a major tournament since the 1998 World Cup in France and victory over Liechtenstein would see them with four points from two games following last Friday's goalless draw in Lithuania as Craig Levein's men target a place in Ukraine and Poland.
On a mission: Fletcher (left) wants to lead Scotland to Poland and Ukraine in 2012
With world champions Spain and Czech Republic also in qualifying Group I, Fletcher is aware failure to defeat Liechtenstein would be disastrous.
'With respect for qualifying for Euros, then there can be no slip-ups,' said the Scotland captain.
'If we can get three points (against Liechtenstein) and then four points from the two games, then it's a satisfactory start and it's not too bad a position from then on.
'We've got games coming up against Czech Republic and Spain, so that's why it's imperative against Liechtenstein to get three points.
'Anything other than that is disastrous towards qualifying.'
Fletcher made his debut in August 2003 away to Norway and is yet to taste competitive action at a major tournament.
'I've been very fortunate to build up this many caps so far and hopefully I can get many more caps and win those caps at a major championships,' added the 26-year-old from Dalkeith.
Good old days: Colin Hendry skippered the Scots at the 1998 World Cup
'I think that's the biggest thing when you represent your country - first and foremost is qualifying for a tournament.
'That's what all my focus is on and not selfish reasons trying to build up caps.
'My focus coming here is to play for my country, enjoy representing my country and try and qualify for a major tournament.'
Sir Alex Ferguson offered his congratulations as Fletcher left Manchester United for the international break, but the midfielder will wait until after the game to reflect on his international career thus far.
Fletcher added: 'We spoke about it before we left and he said "enjoy the moment".
'It is hard to enjoy the moment, because my focus is on winning the game.
'Hopefully with the three points and a nice win I can look back and enjoy the fact that I've gained 50 caps for my country and be very proud of that.'
Lithuania 0 Scotland 0: Livid Levein! Scots boss lashes out after false startSign up to our FREE Fantasy Football game - with £40,000 in prize money up for grabsFletcher's Scotland role under threat after Wolves striker's foot injuryDon't worry about Davie! Weir's brain makes up for lack of pace - HoustonMANCHESTER UNITED FC