Sahih al-Bukhari, Book 18, Hadith 29 (In-Book) ⓘ

Narrated Az-Zuhri: Salim told me, "`Abdullah bin `Umar said, 'I saw Allah's Messenger delaying the Maghrib prayer till he offered it along with the `Isha prayer whenever he was in a hurry during the journey.' " Salim said, "Abdullah bin `Umar used to do the same whenever he was in a hurry during the journey. After making the call for Iqama, for the Maghrib prayer he used to offer three rak`at and then perform Taslim. After waiting for a short while, he would pronounce the Iqama for the `Isha' prayer and offer two rak`at and perform Taslim. He never prayed any Nawafil in between the two prayers or after the `Isha' prayers till he got up in the middle of the night (for Tahajjud prayer)."

حَدَّثَنَا أَبُو الْيَمَانِ، قَالَ أَخْبَرَنَا شُعَيْبٌ، عَنِ الزُّهْرِيِّ، قَالَ أَخْبَرَنِي سَالِمٌ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ ـ رضى الله عنهما ـ قَالَ رَأَيْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم إِذَا أَعْجَلَهُ السَّيْرُ فِي السَّفَرِ يُؤَخِّرُ صَلاَةَ الْمَغْرِبِ، حَتَّى يَجْمَعَ بَيْنَهَا وَبَيْنَ الْعِشَاءِ‏.‏ قَالَ سَالِمٌ وَكَانَ عَبْدُ اللَّهِ يَفْعَلُهُ إِذَا أَعْجَلَهُ السَّيْرُ، وَيُقِيمُ الْمَغْرِبَ فَيُصَلِّيهَا ثَلاَثًا، ثُمَّ يُسَلِّمُ، ثُمَّ قَلَّمَا يَلْبَثُ حَتَّى يُقِيمَ الْعِشَاءَ، فَيُصَلِّيهَا رَكْعَتَيْنِ، ثُمَّ يُسَلِّمُ وَلاَ يُسَبِّحُ بَيْنَهَا بِرَكْعَةٍ، وَلاَ بَعْدَ الْعِشَاءِ بِسَجْدَةٍ حَتَّى يَقُومَ مِنْ جَوْفِ اللَّيْلِ‏.‏