Last Sunday, Bubba Watson closed with a 66 at the Hero World Challenge to win by three strokes over Patrick Reed. For some, the Hero World Challenge represents the conclusion of not only the silly season for PGA Tour players, but professional golf as a whole for the calendar year. In that spirit, it seems to be a fitting time and opportunity to look back on 2015 on the PGA Tour in order to come to grips with the lessons learned this past year.

The Big Cat is running out of lives

Depending on who you ask, Eldrick Tont “Tiger” Woods is the greatest professional golfer of all time. As Tiger himself has pointed out, it is, in reality, impossible to compare players across eras. While he passed Jack Nicklaus with respect to PGA Tour career wins, Tiger has contrarily failed to pass the Golden Bear in terms of professional major wins. Tiger turns 40 years old later this month and last won on the PGA Tour in August 2013 at the WGC-Bridgestone Invitational. The question for now remains whether he will play again on the PGA Tour, let alone win, or even compete for another professional major championship.

Despite seemingly being bulletproof for years, even in the face of self-inflicted personal turmoil, fundamental swing changes, and an ever-present microscope, it appears that time has run out on Tiger. Worn down by a golf swing that produced golf shots impossible to fathom, Tiger is, by all accounts, transitioning into the next phase of his golf life. That role for lack of a better term is simply to be a “living golf legend.”

Players now atop the world golf rankings will forever identify Tiger as the player that inspired them to settle for being nothing less than the best. Whether it is Spieth, McIlroy, Day or some other stone-faced youngster ready to set the PGA Tour on fire, Tiger’s greatest contribution to competitive professional golf may be that he empowered this generation of fearless golfers to play for greatness, not just a paycheck. Tiger, the player, will be missed.

Spieth shows no sign of slowing down

Fresh off a strong defense of his 2014 Australian Open win, Spieth competed, but ultimately fell short in defending his 2014 Hero World Challenge win. Despite failing to repeat at either event, each of which were integral to kickstarting his epic 2014-2015 season, it is nonetheless clear that Spieth can and will be a factor in every tournament he plays.

Rather than taking a prolonged rest this offseason, Spieth has publicly stated that prior to settling in for the holiday season, he will be heading to Augusta National for vacation and a “little work.” Shortly thereafter in January 2016, Spieth is heading to both Abu Dhabi and Singapore for international events before returning to the PGA Tour at the AT&T Pebble Beach National Pro-Am. As world No. 1, Spieth, like a young Tiger, is taking his talents worldwide in an effort to build upon his success, rather than merely revel in it.

Not since the early 2000s on the PGA Tour has there been such excitement about state of men’s professional golf and Spieth is primarily responsible for that unbridled anticipation. Love him, hate him, or undervalue him, Spieth doesn’t seem to care, his job and his goals are unaffected by anything or anyone. It will be difficult to top 2014-2015, but it will be fun to watch Spieth do his best to try.

McIlroy’s “A” game is seemingly unstoppable

It is hard to recall an individual professional golf season, such as McIlroy’s in 2014-2015, with so much success on the course that was so easily forgotten. As a reminder, McIlroy won the 2015 WGC-Cadillac Match Play Championship and Wells Fargo Championship on the PGA Tour and Omega Dubai Desert Classic and DP World Tour Championship on The European Tour, as well as the season-ending Race to Dubai.

Derailed in July by an ankle injury that prevented McIlroy from playing The Open Championship at the Old Course at St. Andrews, McIlroy eventually became an afterthought in the midst of Spieth v. Day’s season-ending duel for PGA Tour Player of the Year and the FedExCup. At age 26, McIlroy still warrants as much attention as anyone in professional men’s golf. As a winner of 11 PGA Tour events, including four professional majors and eight international victories, no current player under the age of 30 can boast of similar credentials and pedigree (even Spieth, not yet at least).

Last year on the PGA Tour, McIlroy averaged 304 yards off the tee, while hitting almost 68 percent of the fairways. There may be no better driver of the golf ball in the world and when McIlroy’s putter cooperates, he is seemingly unbeatable. Head-to-head with Spieth or Day, McIlroy still gets the nod until someone proves otherwise. That said, 2016 with a little luck may just provide answers and those big-time duels that we dream about.

Day may be prove to be top dog

As between Spieth and McIlroy, Day is the elder statesman and at age 28, he may still prove to be the absolute best of the bunch. Admittedly, Day’s resume lags behind both Spieth and McIlroy, given his seven PGA Tour victories and just one professional major. A closer examination of the particulars, however, reveals that six of those victories were recorded in the past two seasons on the PGA Tour, including two victories in the 2015 FedExCup playoffs.

Further, Day arguably possesses the only true all-around game, i.e., one that lacks detrimental competitive weaknesses. Last season, Day finished in the top-10 in driving distance, greens in regulation percentage, strokes gained: tee-to-green, strokes gained: putting, strokes gained: total, birdie average, scoring average, and sand save percentage. He also finished first in the all-around ranking amongst 184 PGA Tour players in total.

When compared to a 22-year-old Spieth, the clock is certainly ticking, so to speak, but Day in conventional terms is just beginning to transition into his prime years on the PGA Tour. Absent injury or something truly unforeseeable, Day may prove to outlast his younger counterparts. Keep in mind, as Spieth and McIlroy move into new eras in their personal lives, Day has already experienced and established himself in that same context. In short, there is a lot of golf to be played and Day’s brilliance is yet to be fully understood or appreciated.

It’s a young man’s game, but age is still just a number

With the exception of Graeme McDowell, recent winner of the 2015 OHL Classic at Mayakoba, every PGA Tour winner after the conclusion of The Playoffs was 31 years old or younger and Justin Thomas was the youngest winner at age 22. Davis Love III, at age 51, closed out the 2014-2015 PGA Tour regular season in style, on the other hand, by winning the 2015 Wyndham Championship. Notwithstanding those tournaments in 2016 where a savvy veteran (like DLIII) ultimately outlasts a much younger counterpart, the trend of new, hungry PGA Tour winners is only going to continue with regularity in the short-term.

Expect a monster year from Patrick Reed in 2016, who, on the strength of six straight top-10 finishes worldwide, has moved in the top-10 of the Official World Golf Rankings. And anticipate wins from players like Rickie Fowler, Brooks Koepka, Justin Thomas, and Patrick Rodgers to become commonplace, as age is simply no longer a factor in forecasting success on the PGA Tour. Mark Twain once said that “age is an issue of mind over matter. If you don’t mind, it doesn’t matter,” and the likes of Fowler, Koepka, Thomas, and Rodgers (and of course, Spieth and Reed, among some others) don’t mind at all.