His career is very much like Keylor Navas'.
Both were never hyped and had to fight and struggle for their chances. That's why both are great under pressure and in big moments. Built up so much resilience nothing fazes them anymore.
Navas went from backup at Levante to winning the job and becoming La Liga's best GK alongside Courtois at Atleti in 2013/14. Emi Martinez went from multiple loan spells and a backup at Arsenal to being 1st choice at Aston Villa when they picked Leno instead of him and was Premier League's best GK last season.