text: After a dreadful first-half showing, Spurs improved and the Wales left-back found the breakthrough against their Championship opponents with a deft header.
  Son Heung-min then wrapped up the victory when he converted Moussa Sissoko's pass to put Mauricio Pochettino's side in Monday's fourth-round draw.
  Tottenham have moved into third place in the Premier League on the back of a five-match winning run, but their second string struggled to click against a Villa side set out to frustrate.
  Without the rested Dele Alli, Harry Kane and Christian Eriksen, the hosts were short of ideas and the tie looked destined for a replay until unlikely goalscorer Davies arrived inside the penalty area.
  Villa mustered one shot on target all game and Steve Bruce will now turn his attention to overhauling a seven-point gap to the Championship play-off places.
  Tottenham were excellent in beating Premier League leaders Chelsea 2-0 in midweek, but perhaps unsurprisingly were nowhere near that level in the opening hour.
  Of the XI who started against Chelsea, only Toby Alderweireld and Eric Dier kept their places - and it showed.
  Alli, Kane and Eriksen had contributed 30 of Spurs' 51 goals this season, and 11 of 33 assists, before kick-off and without them Pochettino's side looked toothless.
  Stand-in striker Vincent Janssen, who has scored just three penalties in 23 appearances now, was particularly lightweight and it was only when Alli finally replaced him after an hour that Tottenham found a way through.
  It was another replacement, Georges-Kevin Nkoudou, who crossed for Davies to head home before Son - who had moved up front once Janssen went off - buried the second.
  A top-four finish remains Pochettino's most pressing assignment, but after a dismal Champions League campaign a first FA Cup win since 1991 should also be high on his list.
  More to follow.
  Match ends, Tottenham Hotspur 2, Aston Villa 0.
  Second Half ends, Tottenham Hotspur 2, Aston Villa 0.
  Corner,  Tottenham Hotspur. Conceded by Sam Johnstone.
  Attempt saved. Son Heung-Min (Tottenham Hotspur) right footed shot from the centre of the box is saved in the centre of the goal. Assisted by Josh Onomah.
  Hand ball by Aaron Tshibola (Aston Villa).
  Attempt blocked. Ross McCormack (Aston Villa) right footed shot from outside the box is blocked.
  Foul by Georges-Kévin Nkoudou (Tottenham Hotspur).
  Aaron Tshibola (Aston Villa) wins a free kick in the attacking half.
  Attempt missed. Ross McCormack (Aston Villa) right footed shot from outside the box is just a bit too high from a direct free kick.
  Foul by Cameron Carter-Vickers (Tottenham Hotspur).
  Jack Grealish (Aston Villa) wins a free kick in the attacking half.
  Attempt missed. Josh Onomah (Tottenham Hotspur) right footed shot from the centre of the box misses to the right.
  Substitution, Tottenham Hotspur. Josh Onomah replaces Moussa Sissoko.
  Offside, Aston Villa. Aaron Tshibola tries a through ball, but Ross McCormack is caught offside.
  Foul by Ben Davies (Tottenham Hotspur).
  Leandro Bacuna (Aston Villa) wins a free kick on the right wing.
  Goal!  Tottenham Hotspur 2, Aston Villa 0. Son Heung-Min (Tottenham Hotspur) right footed shot from the centre of the box to the centre of the goal. Assisted by Moussa Sissoko.
  Eric Dier (Tottenham Hotspur) wins a free kick on the right wing.
  Foul by Jack Grealish (Aston Villa).
  Attempt saved. Moussa Sissoko (Tottenham Hotspur) right footed shot from the left side of the box is saved in the centre of the goal. Assisted by Ben Davies.
  Offside, Tottenham Hotspur. Harry Winks tries a through ball, but Son Heung-Min is caught offside.
  Substitution, Aston Villa. Ross McCormack replaces Gabriel Agbonlahor.
  Substitution, Aston Villa. Keinan Davis replaces Mile Jedinak.
  Substitution, Aston Villa. Andre Green replaces Albert Adomah.
  Ben Davies (Tottenham Hotspur) wins a free kick in the defensive half.
  Foul by Aaron Tshibola (Aston Villa).
  Kieran Trippier (Tottenham Hotspur) wins a free kick in the defensive half.
  Foul by Jordan Amavi (Aston Villa).
  Attempt missed. Eric Dier (Tottenham Hotspur) right footed shot from outside the box is too high. Assisted by Ben Davies.
  Attempt blocked. Eric Dier (Tottenham Hotspur) right footed shot from outside the box is blocked.
  Kevin Wimmer (Tottenham Hotspur) wins a free kick in the attacking half.
  Foul by Gabriel Agbonlahor (Aston Villa).
  Corner,  Tottenham Hotspur. Conceded by Jordan Amavi.
  Goal!  Tottenham Hotspur 1, Aston Villa 0. Ben Davies (Tottenham Hotspur) header from the centre of the box to the bottom right corner. Assisted by Georges-Kévin Nkoudou with a cross.
  Attempt missed. Jack Grealish (Aston Villa) right footed shot from more than 40 yards on the left wing misses to the left from a direct free kick.
  Substitution, Tottenham Hotspur. Georges-Kévin Nkoudou replaces Toby Alderweireld.
  Foul by Cameron Carter-Vickers (Tottenham Hotspur).
  Jack Grealish (Aston Villa) wins a free kick in the attacking half.
  Attempt saved. Harry Winks (Tottenham Hotspur) right footed shot from outside the box is saved in the bottom left corner. Assisted by Dele Alli.
  Attempt missed. James Chester (Aston Villa) header from the left side of the box misses to the left. Assisted by Albert Adomah with a cross following a corner.
target: Ben Davies scored his first goal for Tottenham as the eight-time winners ground out an FA Cup third-round win over a stubborn Aston Villa side.