Quantitative methods in the domain of player experience evaluation provide continuous and real-time analyses of player experiences. However, current quantitative methods are mostly either too confined within in-game statistics, or require non-typical laboratory play setups to monitor real-life behavior. This paper presents preliminary results on the feasibility of using facial expressions analysis as a natural quantitative method for evaluating player experiences. Correlations were performed between the facial expressions intensities and self-reported Game Experience Questionnaire (GEQ) dimensions of players in two video games.