It been a while since Real Sociedad had a consistent win in a row but there is something odd this time, you can see how fast they are approaching Real Madrid and Barcelona but it will be difficult task for them to achieve that goal, perhaps they can switch between Real Madrid but I doubt if they will go to the top of the standing.
compared to Madrid and Barcelona, real Sociedad has perfect results of 5 consecutive wins, and the difference in points between Sociedad and Madrid is also getting smaller, Sociedad could have shifted Madrid's position until the end of the season if Sociedad continues to win, who knows!
Real Sociedad is a real threat to Real Madrid and Barcelona now, they are doing very well in every game they run. If they can maintain their impressive form then it is very possible for them to overtake Real Madrid and Barcelona in the standings, while waiting for the two strong clubs to slip in their matches. Because, if we look at what has happened this season, it is very possible that Real Madrid and also Barcelona will lose points from the club they are facing. Their task now is to maintain what they have achieved so far.