Najib Khan locked the main Maratha army under Dattaji Shinde at Sukkartal. In the meanwhile two Afghan armies advanced, one under Jahan Khan who descended through Khyber Pass with 20000 and the other under Ahmed Shah Abdali through Bolan Pass with 40000. It was joined first by the army of Qalat, Afghans on this side of Khyber and Rohillas. Marathas, who should have been ready, were completely taken unawares. The long flight of Marathas started around 1st of November 1759 till they reached Sukkartal on 8 Nov 1759. On comparision, Sirhind which was one of their stopping point, fell to Afghans on 27 Nov 1759. Below is a charting of their long flight. To their credit, they did not fight even a single battle(there was but one skirmish near Rohtas) in all their path from the borders of Afghanistan to North Western Uttar Pradesh. Instead of they flying, had Dattaji Shinde advanced and met them, was there a possibility that Abdali would have stopped well ahead of Panipat?

1. A Maratha force of 6000 under Bapuji Tryambak, surprised on seeing Afghans retreat from Multan
2. Seeing Jahan Khan descending through the passes, Sabaji Patel retreats from Peshawar to Attock. Compare this with Bhimapala who held the pass against Ghazni with all he got.
3. Sabaji Patel joins forces with Tukoji Shinde at Attock. Both of them retreat towards Lahore
4. Maratha party surprised by Jahan Khan near Rohtas, they bypass Lahore and move toward Batala.
5. Meanwhile, the Maratha contingent of Lahore under Naro Shankar and Narsoji Pandit leaves Lahore for Batala.
6. Both the armies merge at Batala and continue their flight to Sirhind through Jullundhur. While crossing Sutlej, they are attacked by marauders and are looted. I believe, going by the numbers at Multan, they would have had atleast 20-25000 seasoned troops with them along with good leaders and with their hit and run mode of fight, would have made Abdali think seriously of retreat. No telling as to what will happen if Sikhs combine with them. Or even, they would have held out if they cooped themselves Sirhind or the like.
7. They finally reached Sukkartal on 8th Sep 1759.

And again, it’s the same Naro Shankar who fled from Delhi after Panipat instead of stabilizing the line or securing those fleeing from the battlefield of Panipat.

But the fact is that they finally stood up and gave a tough time for the Afghans, evne losing their generallismo. Had they stood up early, the world history may have changed completely.

Even, the story of the flight doesn’t end there –
1. A skirmish near Tarain, Marathas lose but Abdali runs away
2. Abdali reaches Luni, Dattaji reaches Burari, no information coming regarding Afghans as they were killing every Indian coming near them while they had complete information over Maratha movements due to Najib Khan
3. Probing action at Burari Ghat, Dattaji, instead of staying back, advances and is killed along with his brother Jotiba. Jankoji Shinde is seriously injured. Maratha losses 1000
4. Seeing the fall of their commander, Maratha army of 60000 disperses and flees to Kotputli where Malhar Rao Holkar consolidates the armies. Don’t they have even a single commander who can handle 60000 – Naro Shankar, Sabaji Patel, Tukoji Shinde, Govind Pant Bundele, Antaji, Narsoji Pandit?
5. The fleeing army merges with that of Holkar’s forces at Kotputli. Is it 60000 or 75000 now? They advance to Delhi but when he comes to know Abdali is marching on Delhi to counter Holkar, he runs away to Ganga Doab to loot Najib Khan’s lands
6. Sikandarabad looted, Maratha advanced guard defeated by Afghans when they were busy plundering. Malhar Rao runs away to Agra.

Basically, their field armies in North were not touched. What just happened to force Nanasaheb to send the field army of the south to counter Abdali? How come the Marathas had 60000 in Panipat when their total North Indian Army had atleast 50000 and Southern Army, another 50000? Does that mean the army dispersed and the field commanders were not in a position to discipline their soldiers?

This is the information I was able to get hold of. Please correct me in case there are any mistakes.