== Deltagere ==
=== Single ===
{| class="wikitable"; align="right" style="font-size:90%;" text="justify"
! colspan="5" | Singlelisten for året
|-
! Plads 
! width="175" | Navn
! Point
! width="20" | Turneringer
! width="100" | Kvalifikationsdato
|-
| align="right" | 1 || {{flagikon|SUI}} [[Roger Federer]] || 10150|| align="center" | 15 || align="center"| 5. juli<ref name = "Federer">{{Cite web |work=ATP Official website |title=Federer & Top Doubles Teams Qualify For Barclays ATP World Tour Finals |url=http://www.barclaysatpworldtourfinals.com/en/news/federerqualifies.asp |date=2009-07-06 |access-date=2009-07-06 |archive-date=10. juli 2009 |archive-url=https://web.archive.org/web/20090710023028/http://www.barclaysatpworldtourfinals.com/en/news/federerqualifies.asp |url-status=dead }}</ref>
|- bgcolor="#e5d1cb"
| align="right"| 2 ||{{flagikon|ESP}} [[Rafael Nadal]] || 9205 || align="center" | 17 || align="center"| 19. maj<ref>{{Cite web |work=ATP Official website |title=Nadal Qualifies For Barclays ATP World Tour Finals As Tickets Go On Public Sale |url=http://www.barclaysatpworldtourfinals.com/EN/NEWS/NADALQUALIFIES.ASP |date=2009-05-19 |access-date=2009-05-20 |archive-date=11. juni 2009 |archive-url=https://www.webcitation.org/5hSNvBnAg?url=http://www.barclaysatpworldtourfinals.com/EN/NEWS/NADALQUALIFIES.ASP |url-status=dead }}</ref>
|- bgcolor="#e5d1cb"
| align="right" | 3 || {{flagikon|SRB}} [[Novak Djokovic]] || 7910 || align="center" | 22 || align="center"| 10. september<ref name = "Djokovic">{{Cite web |work=ATP Official website |title=Djokovic & US Open Doubles Finalists Qualify For Barclays ATP World Tour Finals |url=http://www.barclaysatpworldtourfinals.com/en/news/djokovicqualifies.asp |date=2009-09-10 |access-date=2009-09-10 |archive-date=13. september 2009 |archive-url=https://www.webcitation.org/5jkP58rSd?url=http://www.barclaysatpworldtourfinals.com/en/news/djokovicqualifies.asp |url-status=dead }}</ref>
|-
| align="right"| 4 || {{flagikon|GBR}} [[Andy Murray]] || 6630 || align="center"| 18 || align="center"| 20. august<ref>{{Cite web |work=ATP Official website |title=Murray Qualifies For Finals; Buy Tickets |url=http://www.atpworldtour.com/News/Tennis/2009/08/Murray-Qualifies.aspx |date=2009-08-21 |access-date=2009-08-21 |archive-date=26. august 2009 |url-status=live |archive-url=https://web.archive.org/web/20090826184952/http://www.atpworldtour.com/News/Tennis/2009/08/Murray-Qualifies.aspx }}</ref>
|- bgcolor="#e5d1cb"
| align="right"| 5 || {{flagikon|ARG}} [[Juan Martín del Potro]] || 5985 || align="center"| 19 || align="center"| 15. september <ref>{{Cite web |work=ATP Official website |title=US Open Champion del Potro Qualifies For Barclays ATP World Tour Finals |url=http://www.barclaysatpworldtourfinals.com/en/news/delpotroqualifies.asp |date=2009-09-15 |access-date=28. november 2009 |archive-date=24. september 2009 |archive-url=https://web.archive.org/web/20090924003029/http://www.barclaysatpworldtourfinals.com/en/news/delpotroqualifies.asp |url-status=dead }}</ref>
|-
| align="right" | (skadet) || {{flagikon|USA}} [[Andy Roddick]] || 4410 || align="center" | 17 || align="center"| 20. oktober<ref>{{Cite web |work=ATP Official website |title=Roddick Secures Berth At Barclays ATP World Tour Finals |url=http://www.barclaysatpworldtourfinals.com/en/news/roddickqualifies.asp |date=2009-10-20 |access-date=28. november 2009 |archive-date=23. oktober 2009 |archive-url=https://web.archive.org/web/20091023050916/http://www.barclaysatpworldtourfinals.com/en/news/roddickqualifies.asp |url-status=dead }}</ref>
|- bgcolor="#e5d1cb"
| align="right" | 6 || {{flagikon|RUS}} [[Nikolaj Davydenko]] || 3630 || align="center" | 22 || align="center"| 12. november<ref>{{Cite web |work=ATP Official website |title=Davydenko, Two Doubles Teams Qualify For Barclays ATP World Tour Finals |url=http://www.atpworldtour.com/News/Tennis/2009/11/Finals-Davydenko-Qualifies.aspx |date=2009-11-12 |access-date=28. november 2009 |archive-date=15. november 2009 |url-status=live |archive-url=https://web.archive.org/web/20091115081352/http://www.atpworldtour.com/News/Tennis/2009/11/Finals-Davydenko-Qualifies.aspx }}</ref>
|- 
| align="right" | 7 || {{flagikon|ESP}} [[Fernando Verdasco]] || 3300  || align="center" | 24  || align="center"| 13. november<ref name="Verdasco">{{Cite web |work=ATP Official website |title=Verdasco & Poles Complete Barclays ATP World Tour Finals Fields |url=http://www.atpworldtour.com/News/Tennis/2009/11/Finals-Verdasco-Qualifies.aspx |date=2009-11-13 |access-date=28. november 2009 |archive-date=17. november 2009 |url-status=live |archive-url=https://web.archive.org/web/20091117111123/http://www.atpworldtour.com/News/Tennis/2009/11/Finals-Verdasco-Qualifies.aspx }}</ref>
|-
| align="right" | 8 || {{flagikon|SWE}} [[Robin Söderling]] || 3010  || align="center" | 26  || align="center"| 17. november<ref name="Söderling">{{Cite web |work=ATP Official website |title=Robin Söderling  To Make Barclays ATP World Tour Finals Debut |url=http://www.atpworldtour.com/News/Tennis/2009/11/Finals-Söderling -Elevated.aspx|date=2009-11-17 }}</ref>
|-
|}
De otte singledeltagere kan ses i tabellen sammen med tidspunktet for deres sikring af pladsen. 
Som reserver til deltagelse i turneringen er de næste fra listen også i London; det drejer sig om listens nummer ti, [[Jo-Wilfried Tsonga]], og nr. elleve, [[Fernando González]].
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