Is Federer's 2017 Season His Best Start Ever?

06 Apr 2017

After the first quarter of the 2017 season, Roger Federer has his 18th Grand Slam title and a 19-1 win record overall. Such an impressive start naturally leads us to ask: Where should we rank Federer’s 2017 start against the other seasons of his career? How does it compare to the best season starts in tennis history?

Tennis Australia’s Game Insight Group has scoured the first three months of the men’s Open Era to try to shed light on these questions. Certainly we all have our personal favorites, but we at GIG wanted to take a more objective approach to identifying the best season starts in tennis history. So we use statistics.

The actual statistic we developed is a cumulative win score that not only considers a player’s total wins and losses but also the difficulty of the opponents faced. Not all draws are created equal and neither are win records. We acknowledge this by giving players more credit for wins against tough opponents and greater penalties for losses against weaker opponents.

But how exactly do we score a match result to reflect the difficulty of the opponent?

We incorporate opponent difficulty into our score by using player Elo ratings. Elo ratings are a type of power ranking that have been used throughout sport for decades. In tennis, an Elo rating is a number that reflects a player’s strength at any given time, accounting for all of the player’s career wins and losses and giving greater weight for wins over the hardest opponents, while penalizing more heavily for surprising losses. Players who just enter the tour begin at a rating of 1500 and that grows as they add to their win record. Roger Federer’s career peak Elo was a high of 2,524, which he reached in 2007. His current Elo is 2,373.

One of the strengths of Elo ratings is that, given a player’s current Elo rating, there is a fairly simple formula that can tell us that player’s chance of winning against any Elo-rated opponent. Moreover, the accuracy of Elo predictions have been shown to outperform predictions based on ATP World Rankings by as much as 10%. And this is the main reason why we don’t simply assign a score based on ranking points. You can read more about Elo ratings and how they are used in tennis on the Tennis Abstract and on FiveThirtyEight.

To score a season start, we gather all match results in the first quarter of the season and give a point score to each match win and loss using an Elo-based win prediction. Players gain the most point for wins against the hardest opponents and get the most points deducted for losses against the weakest opponents. Because of the importance of Majors, we also increase gains and loses by 25% for Grand Slam matches.

Using this approach, we scored all men’s season starts in the Open Era and found the top 10 with the highest score at the end of the first quarter. Those 10 seasons are shown in the plot below, ranked from the first to last from top to bottom. Here, we show the cumulative score from first to last match thru the month of April. For comparison, we also include the cumulative score for Roger Federer’s 2017 season.

The top two spots go to Federer’s back-to-back seasons in 2005 and 2006, where he started with a nearly flawless 31-1 and 28-1 win records, respectively. In 2005, Federer raked up 581 points for his wins by the end of the Miami Open, including finals wins over Rafael Nadal in Miami (in a repeat of this year) and three other final wins over his current coach Ivan Ljubicic. His only defeat was in the Australian Open to a strong Marat Safin.

Although Federer took the Australian Open title for the first time in 2006, his overall score for that season comes in a bit under owing to an easier AO draw in 2006 and for playing one fewer event in the first quarter than the previous year.

The only season before 2000 to feature in the top 10 goes to Pete Sampras’ impeccable 1994 season, which takes the number 3 spot for all-time best season starts. Sampras faltered at the start, with an uncharacteristic first round lost in Doha. But he quickly rebounded, tearing up the AO Series with title wins in Sydney and the Australian Open. Sampras’ second and only other loss in the first quarter was again at a lower-tier event. But, just like Down Under, Sampras played his best in the biggest events and swept the next two Masters events against an impressive field.

Some might be surprised that Djokovic’s inhuman start in 2011 doesn’t get higher than the 5th spot in our list. Although Djokovic had no losses in the first quarter, he played fewer events that year than most other top players. On balance going deep in one or two extra events makes for a more impressive overall performance in our scoring system, even if it comes with a late-stage loss.

Others might wonder why past legends like Jimmy Connors or Guillermo Vilas don’t feature among the best starts. Though some of the top players in the first decades of the Open Era played extensively, there are two main reasons that the top players in the past 20 years tend to rise to the top by comparison with out scoring system. First, the Australian Open wasn’t regularly on the schedule of many overseas players until the 1990s. Second, the depth of the men’s game has generally improved over time and the depth in Elo ratings today just doesn’t compare to what it was 30 years ago. So, even though Jimmy Connors won 40 matches by the end of the first quarter in 1974, his total season score was just 406.

Season Start	Match Win-Loss	Set Win-Loss	Game Win-Loss	Score
Roger Federer 2005	31-1	70-11	489-300	581
Roger Federer 2006	28-1	66-9	448-268	541
Pete Sampras 1994	28-2	65-15	456-306	475
Novak Djokovic 2015	24-2	56-12	408-247	473
Novak Djokovic 2011	22-0	50-5	325-156	453
Andy Roddick 2010	26-4	60-17	443-343	444
David Ferrer 2013	25-5	57-21	414-269	442
Rafael Nadal 2009	22-3	53-14	385-254	413
Ivan Ljubicic 2006	24-4	55-16	411-290	404
Novak Djokovic 2007	24-5	55-16	406-261	403

Federer’s 2017 season has been one of the biggest surprises in tennis this year. But with Federer being more selective about events and the one shocking loss to Evgeny Donskoy in the second round of Dubai puts his season start as the 52nd all-time best. Since 2000, the first year Federer competed in the main draw of the Australian Open, his 2017 start comes in 7th among his best, coming in just behind his 2009 season.

Below, we can get more perspective on Federer’s season-by-season evolution and how his 2017 compares. His 2005 and 2006 are clearly the far and above the other starts in his career. But interestingly his 2017 start is right on track with those in terms of his match-to-match score rate. He is simply playing less now than he has before.

Based purely on the quality and number of wins, Federer’s 2017 season has been excellent but far from his best. Still, by focusing only on the results, we are overlooking some critical points of the career context. Few can boast of such a season start at 35 let alone when coming off a 2016 season stopped short by injury. While we haven’t directly accounted for longevity in our season start score, when we consider his score in light of where Federer is in his career, it does add dimension to the impressiveness of his 2017 achievements so far.

Season Start	Match Win-Loss	Set Win-Loss	Game Win-Loss	Score
Roger Federer 2005	31-1	70-11	489-300	581
Roger Federer 2006	28-1	66-9	448-268	541
Roger Federer 2004	21-2	49-9	337-205	395
Roger Federer 2011	21-4	48-12	339-228	389
Roger Federer 2014	21-4	50-14	365-245	386
Roger Federer 2009	17-4	45-13	325-228	317
Roger Federer 2017	19-1	46-11	336-236	309
Roger Federer 2002	20-6	48-18	378-302	277
Roger Federer 2015	15-2	34-8	242-152	274
Roger Federer 2007	14-2	36-6	254-168	265
Roger Federer 2003	20-6	47-17	359-261	258
Roger Federer 2001	19-6	43-21	355-288	244
Roger Federer 2010	13-3	35-10	262-175	239
Roger Federer 2013	13-4	34-13	262-194	233
Roger Federer 2016	8-2	22-7	157-104	163
Roger Federer 2008	10-4	27-11	218-159	156
Roger Federer 2000	13-7	30-18	260-219	107

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