If the Prophet (PBUH) was in a hurry to travel, he would combine Al-Maghrib and Al-'isha' prayers.

Salamah ibn Kuheil said: I saw Sa'eed ibn Jubeir at Al-Muzdalifah. He established the prayer, then he prayed Al-Maghrib prayer three rak'ahs and said tasleem [concluding the prayer], then he prayed Al-'isha' prayer two rak’ahs. Saeed narrated that 'Abdullah ibn 'Umar prayed it in this place and he did the same, and Ibn 'Umar narrated that the Messenger of Allah (PBUH) did the same in this place.