Roger Federer’s 2018 season ends in the semifinals of the ATP Finals. Alexander Zverev advances to the final, 7-5 7-6 (5). Federer finishes with a 48-10 record, 4 titles, 1 grand slam. 310 weeks at #1, 99 titles, 20 grand slams, and counting. 📸 ATP pic.twitter.com/vrGZzacAHs

— FedFan (@FedererFan07) November 17, 2018

Zverev: Again, I'm very sorry that this happened. I didn't mean to upset anybody. I mean that's all I can say: Sorry! pic.twitter.com/tSGCj1ZvUT

— Reem Abulleil (@ReemAbulleil) November 17, 2018

🎾Alexander Zverev beats Roger Federer 7-5 7-6 and makes the final of the #ATPFinals pic.twitter.com/WdC08GetBV

— Coral (@Coral) November 17, 2018

Alexander #Zverev in FINAL!

The German player beats Roger Federer 7-5 7-6 to reach his 1st final at the Masters #ATPFinals pic.twitter.com/i6CPcb1q4d

— We Are Tennis (@WeAreTennis) November 17, 2018

Crowd boos. Zverev: ”1st of all I'd like to apologize for the situation in the tiebreak. The ballboy dropped the ball so it's in the rules that we have to replay the point.”

Croft tells crowd they shouldn't be booing. ”I think you have to be a little bit more respectful” pic.twitter.com/z11vVWF0Kr

— Reem Abulleil (@ReemAbulleil) November 17, 2018

Oh my god, Zverev getting booed.

— José Morgado (@josemorgado) November 17, 2018

If you were booing at the end of the #Federer #Zverev match you are an idiot.

Great win for Sascha, he did nothing wrong apart from play like a superstar. #ATPFinals

— Andrew Castle (@AndrewCastle63) November 17, 2018

ZVEREV WINS!

He wraps up the second set through a tense tie break.

7-5, 7-6

LIVE reaction on @BBCTwo and online: https://t.co/xvwuO8Sj0M #bbctennis #ATPFinals pic.twitter.com/auh8kOCOCX

— BBC Tennis (@bbctennis) November 17, 2018

Boos ring around the arena after Zverev knocks Federer out of the #ATPFinals

"He was only playing by the rules."

You have to feel for Alexander.

LIVE reaction on @BBCTwo and online: https://t.co/xvwuO8Sj0M #bbctennis pic.twitter.com/oukdmtpHum

— BBC Tennis (@bbctennis) November 17, 2018

MATCH POINT: Sascha Zverev steps us in style against @rogerfederer to reach his first #NittoATPFinals title match 👊

🎥 @TennisTV #SuperSaturday pic.twitter.com/Pg9dCqPJT0

— ATP Tour (@atptour) November 17, 2018

Absolutely fantastic how Zverev handled the situation. I would have lost it.

— Svenja Mastroberardi (@svenja_mastro) November 17, 2018

Federer has fallen to Zverev 7-5 7-6(7-5) at the tour finals in London #atp #tennis #federer #zverev #02 #london pic.twitter.com/Up1biKPGTM

— Game Set and Chat (@GameSetandChat) November 17, 2018

🇩🇪 Alexander Zverev is 21-years-old

✅Already World Number 5
✅ Beat Roger Federer
✅ Into the #ATPFinals

👏The future of tennis pic.twitter.com/ztC1Se1qq6

— William Hill (@WilliamHill) November 17, 2018

🎾| He's only gone and done it!!! 🤯

Alexander #Zverev beats great Roger #Federer to reach his first ever ATP Finals Final! 👏

🇩🇪A. Zverev 7-5 7-6(5) R. Federer🇨🇭

Congratulations! pic.twitter.com/QocRfsAMsQ

— SofaScore🌐 (@SofaScoreINT) November 17, 2018

Not the same scale as Osaka but shades of her US Open win in way Zverev looks apologetic for having won. He's really shaken up by the crowd's booing. Totally unfair. https://t.co/xaokZxu0uV

— Charlie Eccleshare (@CDEccleshare) November 17, 2018

21 year old Alexander Zverev defeats Roger Federer 75, 76(5) to reach the final of the ATP Finals. He's the youngest to reach the final since DelPo in 2009 and the first German since Boris Becker in 1996. #atpfinals pic.twitter.com/1vOkNpQM5M

— Reem Abulleil (@ReemAbulleil) November 17, 2018

Sascha #Zverev beats Federer in straight sets to move into his first final at the #NittoATPFinals. What a performance! 🔥 pic.twitter.com/pZTL4qPOJL

— HEAD Tennis (@head_tennis) November 17, 2018

Sascha stuns Federer.

Zverev plays a near perfect match to defeat Federer 7-5, 7-6 (5)

Watch #NittoATPFinals → https://t.co/tPoe44C26q pic.twitter.com/BEEZnBfeY3

— Tennis Channel (@TennisChannel) November 17, 2018

The moment Sascha Zverev reached his first final at the #NittoATPFinals… pic.twitter.com/RLmx7Lehjh

— Tennis TV (@TennisTV) November 17, 2018

Roger Federer's 2018 comes to an end with a 48-10 record (after setting a new personal best start of 17-0 in March):

🏆 Australian Open
🏆 Rotterdam
F Indian Wells
R2 Miami
🏆 Stuttgart
F Halle
QF Wimbledon
F Cincinnati
R4 US Open
SF Shanghai
🏆 Basel
SF Paris
SF ATP Finals

— Gaspar Ribeiro Lança (@gasparlanca) November 17, 2018

🎾 *UPSET ALERT* 🎾

Alexander Zverev beats Roger Federer to progress to the final of the #ATPFinals.

Superb tennis from the 21-year-old. pic.twitter.com/K9aUjKRpYh

— bet365 (@bet365) November 17, 2018

Alexander Zverev plays a flawless match to defeat a sometimes sloppy (!) Roger Federer 7-5, 7-6(5) and reach the most important final of his still short career at #NittoATPFinals. pic.twitter.com/ae98z3HWqW

— Gaspar Ribeiro Lança (@gasparlanca) November 17, 2018

What a rally and what a performance from Alexander Zverev! 🔥🎾

He defeats Roger Federer 7-5 7-6 to book his place in tomorrow's final! 🏟

Watch live reaction and analysis on Sky Sports Arena now!

Recap: https://t.co/x9XANTlKaQ pic.twitter.com/4nILCFkqyh

— Sky Sports Tennis (@SkySportsTennis) November 17, 2018

Alexander zverev beats Roger Federer 7-5 7-6 in the semifinals of the nitto atp finals #zverev #semifinal #victory #NittoATPFinals ( Getty ) pic.twitter.com/KwIp4lWufu

— Phil (@tennis_phil) November 17, 2018

Alexander Zverev beats Roger Federer 7-5, 7-6(5) to reach at the #ATPFinals the biggest final of his career. [getty] pic.twitter.com/rPLXsS82gL

— José Morgado (@josemorgado) November 17, 2018

First. #NittoATPFinals. FINAL.

Sascha Zverev stuns Roger Federer 7-5 7-6 to become the first German to reach the final since Becker in 1996! 😮 pic.twitter.com/VIf3GX25Dh

— Tennis TV (@TennisTV) November 17, 2018

Sascha's stunner 👊🏼

Zverev upsets @rogerfederer 7-5, 7-6(5) to reach the #NittoATPFinals championship match 🏆

➡️ https://t.co/q3ar5nNos4#SuperSaturday #ATP pic.twitter.com/Rxp4sivejc

— ATP Tour (@atptour) November 17, 2018