Apart from Al Jazira - superior to Ahli by a point - Baniyas, Al Nasr, Al Shabab and even Al Wasl could feel pressured into adding players of similar stature.
Al Ahli's signing of Quaresma has raised the bar for Pro League
Is January not supposed to be a torturous month for player recruitment? Managers often can be found cursing its constricted confines or the sudden increase in players' valuations.
Yet, as Al Ahli demonstrated on Monday with the shock acquisition of Ricardo Quaresma, there is a (relative) bargain to be had. However, the signing of a footballer who includes on his CV Barcelona, Inter Milan and Porto not only signals the intentions of the Dubai club, but suggests Pro League rivals must now mirror their ambition.
Ahli, third in the standings at the halfway stage in the league, have upped the ante. While Quaresma's temperament is subject to query, his ability, especially in a still-emergent division such as the UAE top flight, remains unchallenged.
Ahli find themselves eight points behind the pacesetters Al Ain, although that seemingly unassailable lead has in recent days assumed a little more insecurity, especially as Ahli hinted at yet more arrivals.
Having perhaps viewed the Quaresma signing with envious eyes, Al Jazira - superior to Ahli by a point - Baniyas, Al Nasr, Al Shabab and even Al Wasl could feel pressured into adding players of similar stature.
During the past few months, Jazira have validated Cosmin Olaroiu's pre-season prediction they represent the greatest threat to Al Ain's hopes of a second successive league crown.
Despite a run of six victories and two draws in their past eight matches, Jazira would be wise in seeking to replace Fernandinho, the wayward Brazilian who took until this week to score his first goal for the club, albeit in a friendly.
David Beckham is rumoured to be on his way back to the English Premier League with West Ham United, and therefore retains an unrealistic aura, but who better to trump Quaresma than the most capped outfield player for England?
The Abu Dhabi side seem a bit creaky in midfield, where Ibrahim Diaky and Subait Khater are coming to the end of their careers, and a dynamic player could aid a side with few worries in defence.
Baniyas, too, may decide to act. Jozef Chovanec can expect to extract more from Mohamed Zidan, the gifted Egyptian whose progress since arriving this summer has been stunted by injury. Zidan, a perfect foil for the prolific Andre Senghor, has featured in only nine league matches.
Baniyas will enjoy their time in the table's final Asian Champions League spot, but recent heavy defeats to Al Ain and Jazira highlight the precariousness of their position. Reinforcements would sustain their challenge.
Should they slip, a collection of Dubai clubs, given the exercise of some courage in the market, would be ready to pounce. Nasr are fifth, but bar two questionable results against Ajman and Dubai, should still be capable of at least testing Jazira. The squad is sparse, though, and the defence needs strengthening. Walter Zenga, the coach, must also consider the value of Nashat Akram and Leonardo Lima, two of Nasr's overseas players who have thus far failed to justify their lofty status.
Shabab and Wasl have grander designs - they are sixth and eighth, respectively - and only investment in quality will facilitate improvement. Most notably, the fast-developing Shabab should look to augment their backline with strong local talent, while at Wasl questions surround the fitness of Mariano Donda, their playmaker.
Meanwhile, Al Wahda, in seventh, have already swelled their ranks with three signings.
This transfer window, distorted by Quaresma's surprise arrival, will test the resolve of those with genuine aspirations, especially as a busier Al Ain can expect to find resources stretched in the season's second segment.
Ahli's ambition may just force their closest competitors to show their hands.
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