The 20-year-old midfielder, who came through the club's youth system, is yet to make his senior debut for the Stamford Bridge side.
Clifford had a loan spell with Colchester United last season, playing 18 games and scoring his first professional goal.
The Glovers will play in the Championship next season, having won the League One playoffs earlier this year.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Liverpool | 19 | 14 | 4 | 1 | 47 | 19 | 28 | 46 |
| 2 | Arsenal | 20 | 11 | 7 | 2 | 39 | 18 | 21 | 40 |
| 3 | Nottingham ForestNott'm Forest | 20 | 12 | 4 | 4 | 29 | 19 | 10 | 40 |
| 4 | Chelsea | 20 | 10 | 6 | 4 | 39 | 24 | 15 | 36 |
| 5 | Newcastle UnitedNewcastle | 20 | 10 | 5 | 5 | 34 | 22 | 12 | 35 |
| 6 | Manchester CityMan City | 20 | 10 | 4 | 6 | 36 | 27 | 9 | 34 |
| 7 | Bournemouth | 20 | 9 | 6 | 5 | 30 | 23 | 7 | 33 |
| 8 | Aston Villa | 20 | 9 | 5 | 6 | 30 | 32 | -2 | 32 |
| 9 | Fulham | 20 | 7 | 9 | 4 | 30 | 27 | 3 | 30 |
| 10 | Brighton & Hove AlbionBrighton | 20 | 6 | 10 | 4 | 30 | 29 | 1 | 28 |
| 11 | Brentford | 20 | 8 | 3 | 9 | 38 | 35 | 3 | 27 |
| 12 | Tottenham HotspurSpurs | 20 | 7 | 3 | 10 | 42 | 30 | 12 | 24 |
| 13 | Manchester UnitedMan Utd | 20 | 6 | 5 | 9 | 23 | 28 | -5 | 23 |
| 14 | West Ham UnitedWest Ham | 20 | 6 | 5 | 9 | 24 | 39 | -15 | 23 |
| 15 | Crystal Palace | 20 | 4 | 9 | 7 | 21 | 28 | -7 | 21 |
| 16 | Everton | 19 | 3 | 8 | 8 | 15 | 25 | -10 | 17 |
| 17 | Wolverhampton WanderersWolves | 20 | 4 | 4 | 12 | 31 | 45 | -14 | 16 |
| 18 | Ipswich TownIpswich | 20 | 3 | 7 | 10 | 20 | 35 | -15 | 16 |
| 19 | Leicester CityLeicester | 20 | 3 | 5 | 12 | 23 | 44 | -21 | 14 |
| 20 | Southampton | 20 | 1 | 3 | 16 | 12 | 44 | -32 | 6 |
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