How strong are the fields in non-Tour events?

Looking for just ball park figures here, obviously there will be a lot of variation. Here are a few questions and a few guesses:

(1) How difficult is it to qualify for the US Open?
The answer obviously depends on the sectional tournament you’re in, but I’m guessing it’s quite a bit more difficult than making the cut at a PGA Tour event. It seems to take about -0.25 SG/round to make the cut in an average PGA Tour event; I’m guessing it takes closer to +1 - +1.5 SG/round to make it through sectionals. So a player like Jason Kokrak might be around 50-50 to make it.

I actually think it’s easier to get in through a smaller sectional than trying to get through the gauntlet in Ohio. But that’s something that bears further study.

(2) How difficult is it to get through Monday Qualifying?
Obviously not every qualifying is like the one for the Phoenix Open (which was basically a 18-hole Korn Ferry Tour tournament) where you probably needed like +3 SG to get in. But I’m guessing it’s still tougher than a Mini Tour event, so you’ll probably need a +1 SG on average.

(3) How tough is it to win a mini-tour event?
I’ve seen some of these fields. The winners are generally former college stars trying to make it to the PGA Tour. Field size is usually 15-30 and only half the players are competitive but you need to go low to win. My guess is 0 SG, though this will vary a lot.

(4) How competitive are the independent events?
There are quite a few 72-hole tournaments with purses ranging from 50-300K that are not part of any tour, like the Pebble Beach Invitational, Colorado State open, Long Beach Open, etc. Many of them are State Championships run by the state golf associations, and have a good list of sponsors. Given the purses, I’m actually surprised that they don’t attract a stronger field than they do. It’s not uncommon for PGA Tour players to participate in these types of events and they usually do not win. I’m guessing +1 SG/round will be pretty competitive, maybe about as tough to win as a Champions Tour event.

(5) How good are the top club pros?
Many top club pros are actually former (or current!) mini tour aces and some were (successful!) PGA Tour pros in the past. Many of them are top players in the independent events. I’m guessing that winning the PGA Club Pro Championship would be on par with winning the biggest independent events, so I’ll guess that +1 SG/round would have a decent chance.

There is a good description of how DG incorporates field strength into their SG numbers here - it’s called true stroked gained.

For example, you estimate that to get through a Monday qualifier it would take about +1 SG on average over the field to get in. With a large field every week, this on the surface looks like it would be pretty hard to do. But you have to incorporate the fact that the players in these events are much lower than a typical PGA tour player.

Let’s take an extreme example and say that Jon Rahm decided to try and Monday Qualify. Rahm averages 1.88 SG/Round (non field adjusted) in 2021. But when you add in the fact that Rahm is averaging 1.8 strokes per round better than the best players in the world each week, it becomes even more impressive. If Rahm were to only play mini tour events the rest of the year, his raw SG numbers would undoubtedly be even better because his competition is weaker and thus his scores versus the average are even larger.

So in your example, is it very difficult for a mini tour player to Monday qualify? Yes, because they are typically playing against players of equal quality each week and averaging +1SG is difficult when doing apples to apples. But would it be difficult for one of the best players in the world? Likely not. So it really depends on “who” is trying to win these events that you’ve listed

By the way, I’m talking about SG as Datagolf defines it, so it’s an apples to apples comparison. So if Rahm averages +1.88 SG/round, I’m guessing he’ll be successful in Monday Qualifying ~60% of the time and a similar rate for US Open sectional qualifying (this one is 36 holes).

I have seen many examples of 0 and +0.5 SG/round golfers trying the US Open qualifying and independent events. They do win at a high rate and almost always finish high, but they seem to succeed less than 50% of the time.