Justin Thomas' third win of the 2017-18 PGA Tour season was also probably his most stress-free. Thomas shot a 1-under 69 in the final round of this week's WGC-Bridgestone Invitational to capture the ninth win of his young career and his first WGC trophy. The round included just one bogey, two birdies and 15 pars, but ended emotionally for J.T. (more on that in a minute).

The No. 3 player in the world finished at 15 under on the week, four clear of Kyle Stanley, who finished runner-up. Thomas showed off every facet of his game in the impressive win as he buoyed himself on Friday with his putter before closing like he started, by hitting preposterously-good drives and approach shots. He finished in the top 15 in three of the four rounds in strokes gained on approach shots. 

For most of the ending on Sunday, Thomas did what the guy who has won at this course eight times -- Tiger Woods -- did to win golf tournaments. He got way out ahead and played defense. He didn't make mistakes. His proximity to the hole on Sunday was the worst it had been all week, but that was likely strategic as all Thomas had to do was hit the middle of greens and two-putt his way to a dump truck full of money.

Maybe because the rout was on and he could enjoy the final few holes, Thomas showed some emotion at the end. His grandparents were both in attendance, and Thomas clearly wanted to win with them there. His grandfather, Paul, played in the 1960 PGA Championship at Firestone Country Club.

"I'm glad I finally played well around here, just in time for it to leave," Thomas told Peter Kostis of CBS Sports. "I got a little choked up when I saw grandma and grandpa over there. It's really cool. They don't get to come out very often anymore. This is my first PGA Tour win with them here, so it's pretty cool."

The victory for Thomas might not have made for exciting television -- he made just two birdies and nobody truly challenged him in his quest for that first WGC title -- but it does mean that he's now backed up his five-win season in 2016-17 with another three wins so far this year. We underrate how difficult it is to present sufficient encores to elite seasons (which is what last year was), but Thomas has made it look fairly simple with maybe the most complete game on tour. It's a game that seems especially built for a course like Firestone.

Thomas came into this week at Firestone, the last event in this course's history, fifth overall in total strokes gained on the PGA Tour but no worse than 51st in any specific category. He is quite feasibly the most consistently great player in every category. There are golfers who are better drivers, better putters and better iron players, but there might not be any who are better across the board than he is right now (the only one that sticks out to me as a challenger is Dustin Johnson). 

Now Thomas will go to Bellerive next week and the 100th PGA Championship looking for his second straight victory at that tournament and with a boatload of confidence from lapping a field that is probably one of the best he'll see all season. With a stretch run of the PGA Championship and a handful of playoff events, Thomas -- who, remember, had three wins this time last year -- could follow up his great season a year ago with an even better one this time around. Grade: A+

Here are the rest of our grades for the Bridgestone Invitational.

Dustin Johnson (T3): D.J. stalled a bit over the first two rounds before shooting a 66 on Saturday to at least get a peek at the leaderboard. Then he went out and made nine 3s on his first 11 holes and looked for a while like 59 or 58 was in play. However, he went in circles coming home and bogeyed the last to shoot 64 and finish T3. My biggest takeaway is that Johnson is literally never out of a golf tournament no matter how far back he his. Johnson trailed by 11 after 36 holes and nearly touched the lead with 43 bogey-free holes to close out this event. He should probably be the favorite next week at Bellerive, and he probably will be. Grade: A-

Rickie Fowler (T17): What a bizarre week for Fowler. He shot a 63 in the first round, and then he followed that with a 74. He bounced back in Round 3 with a 65, and then he shot a 74 in the final round. His strokes gained looked like a seismograph. Grade: B

  • Round 1: T2
  • Round 2: T64
  • Round 3: 1
  • Round 4: T44

Phil Mickelson (T24): After Lefty opened 66-69, he pulled a mini-Tiger (more on that in a minute) and finished with a 72-70. Mickelson said after his round that he needs to work on his short game going into the PGA Championship, and he's probably right. He finished outside the top 40 in strokes gained putting as well as strokes gained around the green but gained strokes on the field with his driver and finished top 10 in approach shots. Oh, and then he offered private dance lessons for anyone who wants them. Grade: B

Tiger Woods (T31): The eight-time winner of this event had one of the worst weekends he's had in recent memory. After a strong open in which he was 6 under after two days, Woods finished with a pair of 73s and tumbled from just outside the top spot on the leaderboard to not even within striking distance. I stand with the group that's curious about how Woods' body will hold up over the final two months of the year as he strains it with the most tournaments he's played since probably 2012. Grade: C+

CBS Sports was with you the entire way Sunday updating this story with the latest scores, highlights and analysis from Round 4 of the WGC-Bridgestone Invitational. If you are unable to view the live updates below, please click here.

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