Borderlands 3 is 2019's biggest box game release in the UK to date.
Sony's PlayStation 4 exclusive Days Gone previously held that title, from all the way back in April.
Last week's other big arrivals, Gears 5 and PES 2020, turned up in the chart in second and third place respectively - but both sold far fewer boxed copies.
Physical sales of Borderlands 3 were more than double the combined physical sales of both Gears 5 and PES - though it's harder to make comparisons with previous games in 2K's shlooter series.
Borderlands 2, which launched in 2012, sold more than twice as many boxed copies during its launch week - though much of the difference here will be made up by Borderlands 3 digital sales.
Gears 5's comparison to Gears 4, released in 2016, is even more stark. The latest entry shifted less than a quarter of the latter's boxed sales. Microsoft does not disclose how many have played Gears 5 since launch via Game Pass, but the fact you can simply sign up to this subscription rather than pay full price will surely have had some impact.
PES 2020 sales were actually up on last year, meanwhile. It sold around 20 per cent more boxed copies than PES 2019.
Greedfall was fifth, Daemon X Machina was 19th, NHL 20 was 36th. The full top 10 lies below:
- Borderlands 3
- Gears 5
- PES 2020
- NBA 2K20
- Mario Kart 8 Deluxe
- Spyro Trilogy
- Crash Team Racing
- Super Mario Maker 2