Luis Diaz's Liverpool season can essentially be split into two halves.
The first period centres around an electric winger who was the Reds' best player in the first couple of months of the Premier League campaign. While Jurgen Klopp's side struggled to put behind them the looming spectre of the previous 63-game term, Diaz was one of few whose efforts did not drop.
A wonderful solo effort at home to Crystal Palace in August saved the 10-man Liverpool from an early Anfield defeat before he contributed two goals in a 9-0 battering of Bournemouth later that month. A superb strike was little more than a consolation in a 4-1 defeat at Napoli in early September as he registered five goals in the opening month of the term.
A knee injury sustained in a challenge with Thomas Partey during a 3-2 defeat to Arsenal on October 10 all but ruined his season, however. After forsaking days off in favour of further rehabilitation work at the club's AXA Training Centre, Diaz appeared to be on the cusp of a post-Christmas return having reported for duty on the club's mid-season trip to Dubai.
He broke down in an early session out in the Middle East, though, and was immediately flown home to undergo surgery on Merseyside, effectively ruling him out for a further three months.
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"He is not in the best possible place [mentally], that is clear," Klopp told the ECHO in Dubai after his side's 3-1 loss to Lyon. "It was a big disappointment for all of us and him as well. It was a nothing situation in training, honestly.
"And he felt something, he didn't feel it a lot the next day but we wanted to be really cautious. So we said: 'come on, let's have a proper look' and then the news came which was a proper smash in the face, but that's it now."
In total, Diaz missed over six months of football, finally returning to the team in mid-April as a late substitute in the 6-1 hammering of Leeds at Elland Road. Two more cameos followed in victories over Nottingham Forest and West Ham before he was given his first start in 203 days against Tottenham later that month.
Diaz took just five minutes to reopen his account for the season, smartly finishing off a cut-back to make it 2-0 in a wild game that eventually finished 4-3 to the Reds. Three more starts came against Fulham, Leicester and Aston Villa but there had long been a general acceptance that the Colombia international would not show his best form once more until next season after a full pre-season schedule.
It remains a major case 'what if' where Diaz's season is concerned. Liverpool were robbed of a potent attacking weapon for far too long and were left to rue his absence alongside Diogo Jota and Roberto Firmino during a particularly difficult January.
Had the former Porto winger been fit for the full term, top-four hopes might not have evaporated as they did but the onus is on him now to get back to the sort of form he readily displayed prior to that setback at the Emirates back in October. A fully-fit Diaz will be vital to success next season.
End-of-season rating: 6
