Alli bergabung di sistem muda [[Milton Keynes Dons F.C.|Milton Keynes Dons]] ketika ia berusia 11 tahun.<ref name="BBC Sport 19Sep2014">{{cite web|author=Osborne, Chris|title=MK Dons' Dele Alli has the makings of next Steven Gerrard|url=http://www.bbc.com/sport/0/football/29251977|publisher=BBC Sport|accessdate=25 November 2014|date=19 September 2014}}</ref> Ia membuat debut tim utama pada usia 16 tanggal 2 November 2012, datang sebagai pengganti [[Jay O'Shea]] di menit ke-64 dalam hasil 0-0 melawan klub [[Southern Football League]] [[Cambridge City F.C.|Cambridge City]] di ronde pertama [[FA Cup]] di Milton Road.<ref name="Cambridge City 0-0 MK Dons">{{Cite news | first=Chris | last=Osborne | title = Cambridge City 0–0 MK Dons | url = http://www.bbc.co.uk/sport/0/football/20091781 | publisher= BBC Sport | date = 2 November 2012 | accessdate = 27 February 2013}}</ref> Sentuhan pertamanya di sepakbola profesional adalah operan back-heel.<ref name="BBC Sport 19Sep2014"/> Gol pertamanya datang ketika replay melawan Cambridge 11 hari kemudian, dalam kemenangan 6-1 di [[Stadium mk]] dalam start pertama.<ref name="MK Dons 6-1 Cambridge City">{{Cite news | title = MK Dons 6–1 Cambridge City | url = http://www.bbc.co.uk/sport/0/football/20216720 | publisher= BBC Sport | date = 13 November 2012 | accessdate = 27 February 2013}}</ref> Ia membuat debut liga dalam kekalahan 2–3 atas [[Coventry City F.C.|Coventry City]] tanggal 29 December, dimana ia bermain 71 menit sebelum digantikan oleh [[Zeli Ismail]].<ref name="MK Dons 2-3 Coventry City">{{Cite news | title = MK Dons 2 – 3 Coventry City | url = http://www.bbc.co.uk/sport/0/football/20823148 | publisher= BBC Sport | date = 29 December 2012 | accessdate = 26 June 2014}}</ref> Satu penampilan terakhirnya di [[2012–13 Football League One|Football League One musim 2012-2013]], datang sebagai pengganti [[Patrick Bamford]] di babak kedua dalam pertandingan terakhir musim itu, menang 2-0 atas [[Stevenage F.C.|Stevenage]] di [[Broadhall Way]].<ref name="Stevenage 0-2 MK Dons">{{Cite news | title = Stevenage 0 –2 MK Dons | url = http://www.bbc.co.uk/sport/0/football/22228842 | publisher= BBC Sport | date = 27 April 2013 | accessdate = 26 June 2014}}</ref>
====2013–14Musim season2013–14====
TheMusim 2013–14 season sawmelihat Alli breaksebagai intostarter thesecara MKreguler.Ia Donsmenjadi firststarter teamdalam ongame a regular basis. He started thepertama Dons'firstmusim league match of the seasonitu, aseri 0–0 draw away0-0 atmelawan [[Shrewsbury Town]].<ref name="Shrewsbury Town 0-0 MK Dons">{{Cite news | title = Shrewsbury Town 0–0 MK Dons | url = http://www.bbc.co.uk/sport/0/football/23474989 | publisher= BBC Sport | date = 3 August 2013 | accessdate = 26 June 2014}}</ref> InDalam his firstpenampilan [[EFL Trophy|Football League Trophy]] appearancepertamanya, Alli scoredmencetak togol helpuntuk membantu MK Dons beatmengalahkan [[Northampton Town F.C.|Northampton Town]] 2–0 and thus progress to the seconddan roundlolos ofke theronde tournamentkedua.<ref name="MK Dons 2-0 Northampton Town">{{Cite news | title = MK Dons 2–0 Northampton Town | url = http://www.mkweb.co.uk/Sport/Football/MK-Dons/2013-2014/Match-Reports/Football-Match-report-MK-Dons-2-0-Northampton-Town-20130903214442.htm | publisher= MK Web | date = 3 September 2013 | accessdate = 26 June 2014}}</ref> OnTanggal 28 September, Alli scoredmencetak hisgol firstliga professionalprofesional leaguepertamanya goaldalam in thekemenangan 4–1 thrashing ofatas Stevenage.<ref name="MK Dons 4-1 Stevenage F.C.">{{Cite news | title = MK Dons 4 – 1 Stevenage F.C. | url = http://www.bbc.co.uk/sport/0/football/24184935 | publisher= BBC Sport | date = 28 September 2013 | accessdate = 26 June 2014}}</ref> AfterSetelah beingkeluar inmasuk anddi out of the first team picture in lateakhir 2013 duekarena torentetan injury setbackscedera, Alli wouldmenetapkan godiri onsebagai and establish himself as a first-choicepemain playerstarter indi 2014. HeIa scoredmencetak thegol openingpembuka goaldalam inkemenangan the3-2 3–2 win overatas Shrewsbury Town atdi Stadium mk ontanggal 11 JanuaryJanuari, with adengan header fromdari passing [[Stephen Gleeson]]'s pinpoint pass.<ref name="MK Dons 3-2 Shrewsbury Town">{{Cite news | title = MK Dons 3 – 2 Shrewsbury Town | url = http://www.bbc.co.uk/sport/0/football/25599633 | publisher= BBC Sport | date = 11 January 2014 | accessdate = 26 June 2014}}</ref> OnTanggal 11 MarchMaret, againstmelawan [[Notts County]] atdi [[Meadow Lane]], agedumur 17 yearstahun anddan 11 months oldbulan, Alli scored amencetak hat-trick tountuk guidemembawa the 'Dons to amenang 3–1 victory.<ref name="Notts County 1-3 MK Dons">{{Cite news | title = Notts County 1 – 3 MK Dons | url = http://www.bbc.co.uk/sport/0/football/26428670 | publisher= BBC Sport | date = 11 March 2014 | accessdate = 26 June 2014}}</ref> HisGol nextselanjutnya anddan finalterakhir goaldi ofmusim the 2013–14 season2013-14, camedatang onpada 5 April againstmelawan Coventry City at thedi [[Sixfields Stadium]]; Alli struck a thunderousmencetak volley fromberjarak 25 yardsyard out asdengan MK Dons defeatedmengalahkan Coventry,2–12-1.<ref name="Coventry City 1-2 MK Dons">{{Cite news | title = Coventry City 1 – 2 MK Dons | url = http://www.bbc.co.uk/sport/0/football/26796275 | publisher= BBC Sport | date = 5 April 2014 | accessdate = 26 June 2014}}</ref> HeIa madetampil 37 appearanceskali indi allsemua competitionskompetisi duringketika themusim 2013–14 season2013-14, scoringmencetak 7 timesgol, withdengan 33 appearancespenampilan anddan 6 goals ingol thedi leagueliga.
