There are two ways to correct this: Hold an Iron Ball/Lagging Tail to make you go last. Or (like I do) teach your Ninetales Sunny Day. Sunny Day+Drought is not stupid as it can change the game completely.
You also need probably a second Sunny Day inducer (Virizion comes to mind as he beats opposing Rain/Sand teams most of the times), especially in singles.
As for your question, best physical sun sweeper hands down: Sawsbuck! Has a great movepool and excellent sweeper stats with Chlorophyll. I used him both in singles and in doubles and Saws is the best ^^
Other options: Typhlosion (Choice Specs + STAB + Sun + 150 Base Power Eruption is GOOD), Arcanine (also physical and with a good movepool, but can't hit as hard as Saws since he needs to go Jolly instead of Adamant).