Hadithcore
Sahih Muslim, 2461 a
sahih

Abu Ishaq reported that he heard Abu'l-Ahwas say:

I was along with Abu Musa and Abu Mas'ud as Ibn Mas'ud died and one of them said to the other: Do you find one like him besides him? Thereupon he said: Do you say this (no one can be his rival)? He was admitted (to the company of the Prophet) whereas we were detained and he had been present in the company of Allah's Messenger (ﷺ) whereas we had been absent.

حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، وَابْنُ، بَشَّارٍ - وَاللَّفْظُ لاِبْنِ الْمُثَنَّى - قَالاَ حَدَّثَنَا مُحَمَّدُ، بْنُ جَعْفَرٍ حَدَّثَنَا شُعْبَةُ، عَنْ أَبِي إِسْحَاقَ، قَالَ سَمِعْتُ أَبَا الأَحْوَصِ، قَالَ شَهِدْتُ أَبَا مُوسَى وَأَبَا مَسْعُودٍ حِينَ مَاتَ ابْنُ مَسْعُودٍ فَقَالَ أَحَدُهُمَا لِصَاحِبِهِ أَتُرَاهُ تَرَكَ بَعْدَهُ مِثْلَهُ فَقَالَ إِنْ قُلْتَ ذَاكَ إِنْ كَانَ لَيُؤْذَنُ لَهُ إِذَا حُجِبْنَا وَيَشْهَدُ إِذَا غِبْنَا ‏.‏

References2 variants
In-Book Reference
Book 44, Hadith 159
USC-MSA web (English) reference
Book 31, Hadith 6019 (deprecated numbering scheme)