In chronological order:
1. Djokovic def. Nadal - AO - 5–7, 6–4, 6–2, 6–7, 7–5
A brutal match that cemented Nole's greatness and gave him the chance for a non-CY Grand Slam. Played some phenomenal tennis during the second and third sets but ultimately won the match via determination, durability and a bit of luck.
2. Isner def. Djokovic - IW - 6-7, 6-3, 6-7
Lost another two tie breaks in a big match and an early indication that Nole 2.0 had regressed into Nole 1.5 territory.
3. Nadal def. Djokovic - RG - 4–6, 3–6, 6–2, 5–7
As above, really. Nole's level dropped enough that Rafa won three in a row in clay finals, most importantly at the final of RG of course. Still showed glimpses of supreme tennis - absolutely bossing the fourth set.
4. Murray def. Djokovic - USO - 6–7, 5–7, 6–2, 6–3, 2–6
Another crucial tiebreak loss that set the tone for the first half of the final. Disappointing to see his usually great stamina/fitness let him down a bit in the final set and also disappointed by how long it took him to adapt to the dreadful conditions.
5. Djokovic def. Federer - WTF - 7-6, 7-5
Highly entertaining match of great quality with Nole reinforcing that he's still the best player around by some distance even if he didn't bring his A game at some important moments during the year.
Choosing 3 losses feels weird
But it was an odd year for Nole imo.
sorry but the Djokovic losses on clay this year were less about Djokovic and more about Nadal. Rafa's best on clay is far superior to Djokovic's best on clay, I mean for gods sake Novak has made 1 Roland Garros final IN HIS CAREER. so far less success here than even Robin Soderling
so don't be naive about it