Pakistan has participated in the Asia Cup competition for a total of 15 times (including the recently completed one), and out of this they managed to win the trophy only 2 times. India has won 7 times (50% strike rate) and Sri Lanka is close behind. So there is something wrong with the way the Pakistan team is performing. On one match they are defeating the top ranking team (India) and in the next match they are struggling against a tier-2 test nation. Absence of Shaheen is just an excuse. If that is the case, then India was also missing their strike bowlers.
The problem with team like Pakistan is that whenever they win they don't care what mistake they have done. All focus is on celebrations. Even after Afghanistan win nobody pointed out what went so wrong that team struggled to win against such a weak team. In final Pakistan really don't have a game plan and they deserve to lose.