THE majority of Celtic’s transfer activity so far this month has been focussed at the top end of the pitch with attackers Vakoun Issouf Bayo, Timothy Weah and Oliver Burke recruited so far, and Andrew Gutman brought in as cover at left-back from Chicago Fire. One of these arrivals will likely have a profound effect on the Celtic starting lineup, even if he doesn’t feature too regularly: Timothy Weah, the winger on loan from Paris Saint Germain.

This might sound paradoxical; after all, how can a player influence the team if he’s not playing? But sometimes, a player’s presence alone is enough to have tangible results on the pitch. In this case, it’s Weah’s arrival at Celtic Park that could inspire another player in Brendan Rodgers’ side to finally get his act together after a couple of seasons where his performance levels have continued to slide.

It’s no secret that Scott Sinclair has failed to maintain the level of performance he was regularly putting in during his first season in Glasgow’s east end, but perhaps this is understandable. After all, during the winger’s debut season, Celtic went the entire domestic campaign unbeaten and broke all sorts of records along the way, so this is probably an unfair standard to measure him against. But even comparing Sinclair’s numbers from this season to last, we can see there is a notable drop-off.

As the graphic above illustrates, Sinclair’s stats have declined year on year since he joined Celtic, for the most part. His goalscoring rate has dropped from 0.55 goals in his debut season, then to 0.39 to 0.37. The amount of shots he hits has declined although to be fair, he is hitting them more accurately. The other positive for Celtic fans to take is that Sinclair’s assist rate has remained uniform during his two-and-a-half years at the club, averaging an assist every five games.

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Aside from that, though, it’s bad news wherever else you look. The number of dribbles Sinclair attempts has dropped significantly, as has his success rate at doing so; between this season and last, the winger’s dribbles are 24% less successful. Sinclair’s key passes - a pass that leads to a shot -  per 90 minutes have more than halved since 2016/17 and, while the number of passes into the opposition box he attempts per game have remained around the same, there has been a 20% drop-off in the number that reach their intended target.

Perhaps the most interesting statistic of all is that the number of passes Sinclair receives during any given match has actually risen each season. In short, he’s getting the ball more, doing less with it and doing just about everything less successfully than he has done in the past.

HeraldScotland:

There can be no doubting that Sinclair is only occasionally performing as we all know he can and the last couple of seasons have seen a noticeable decline in the 29-year-old’s influence on the pitch. In all likelihood, the reason for this is relatively straightforward: Sinclair hasn’t had to worry about anyone else taking his place in the team. Complacency has creeped into his game.

As one of the highest-paid members of Brendan Rodgers’ squad, Sinclair is always more likely to play than others in order to justify his wage. It’s a simple fact of football economics that if chairmen are going to splash out on an expensive deal for a player, they need to see some sort of return on it. Of course, this isn’t the be all and end all when it comes to player selection but it is an important factor that shouldn’t be overlooked.

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More pertinently, though, is the fact that Sinclair’s position in the Celtic starting XI hasn’t been under threat because there has been no-one else looking capable of dislodging him from the team. Mikey Johnston has broke into Rodgers’ first-team squad this season but it seems unreasonable to expect the Celtic youth academy graduate to start too many games, given the player’s relative inexperience. Lewis Morgan was brought in in the summer, presumably to provide competition for Sinclair’s spot on the left, but clearly Rodgers feels the 22-year-old isn’t ready for first team football at Celtic yet.

Celtic’s acquisition of Weah until the end of the season ramps up the pressure on Sinclair to raise his level of performance. The PSG wingers wages won’t be insignificant and in order to justify his loan deal, Rodgers will have to play him at some point. The 18-year-old can also play up front as a striker but given the fact that Bayo has also moved to Celtic Park, one would imagine Weah’s place in the Celtic squad will be to provide backup for, or even start ahead of, Sinclair on the left of the attack.

Now that Sinclair has someone who can genuinely challenge him for his place - even if only to justify his loan deal - now is the time for the Englishman to start producing regularly for Celtic again. Weah will leave in the summer but if Sinclair wants to be assured of his place in Rodgers’ starting XI next season then he simply must start playing better. Hopefully the competition provided by Weah will spur him on: if not, then his days at Parkhead could be numbered.