Masters champion Tiger Woods played down an injury scare on the eve of his first appearance since missing the cut in the Open Championship as he attempts to play back-to-back events for just the second time this season.

Woods has committed to play The Northern Trust in New Jersey and the following week's BMW Championship and could make it three weeks in a row if he qualifies for the season-ending Tour Championship in Atlanta, which he won last year for his first victory since 2013.

However, the 43-year-old admits he is concerned about that potential schedule after opting to mainly chip and putt on the back nine of Wednesday's pro-am at Liberty National due to stiffness in his back.

"I was getting stiff and it's best to be smart about it, just kind of what I did pre-Augusta when I went out there and just chipped and putted for nine holes," Woods, who underwent spinal fusion surgery in April 2017, told a pre-tournament press conference.

"I learned a lot last year by playing too much. I pushed it pretty hard and vowed I'd never do that again. I've cut back the schedule quite a bit and that's the challenge now because the season changed.

"Now we've got a more condensed season and it's trying to figure out how to stay sharp, practice and also have my back feeling good all the time.

"I can't practice as much as I'd like, certainly can't even sniff how much I used to practice. Trying to build up to events is more difficult.

"As I said to you guys all year, this is kind of how it is. Some days I'm stiffer than others. Yesterday (Tuesday) I was out there hitting it great with Brooksy (Brooks Koepka) and DJ (Dustin Johnson) and today I'm stiff. Hopefully I'm not that way tomorrow."

Asked about the prospects of playing three weeks in succession, Woods added: "There is concern because given hopefully the pressures I'm going to be facing, hopefully putting myself in contention, that's why it gets difficult. If you're missing cuts who cares, you're taking weekends off.

"I'm trying to get myself where I'm in contention and it takes a toll on you and that's what I want to feel. I want to feel that type of tiredness where I had a chance to win, a chance to win... that's a good feeling."

Woods is ranked 28th in the FedEx Cup standings and needs to remain inside the top 30 to qualify for the Tour Championship, which features a controversial new format.

The player who has the most points after the BMW Championship will start the first round of the Tour Championship on a score of 10 under par.

The second-highest points earner will begin at eight under, the third ranked player at seven under and those who arrive at East Lake in fourth and fifth in the standings will start at six and five under respectively.

The next five players on the list will begin at four under, with scores regressing by one shot for every five players until those ranked between 26th and 30th start the event at level par.

"It's going to be different for all of us," Woods added. "We're trying to make the system perfect, try to make it great for all of us.

"This year's going to be a challenge for all of us. We've all been 10 (shots) back after one day, or with 36 holes to go, but starting out 10 back is going to be different and really puts a premium on placement going into that week, you don't want to give any top player too big a head start."