Bonucci fits the Man City profile perfectly as solid, ball-playing defender
Pep Guardiola is prepared to spend heavily again this summer to put right the shortcomings at Manchester City that have seen them fail to maintain a significant challenge in the Premier League.
In simple terms, the City boss believes that his attackers have not scored enough and his defence has not stopped the opposition from scoring enough, either. "We need to improve in both boxes, both offensively and defensively, to score goals and not concede," he said as far back as November and it's a topic he has returned to throughout the season.
There are reasons to be encouraged about Guardiola's forwards -- not least the emergence of youngsters Leroy Sane and Gabriel Jesus, as well as the return to form of Sergio Aguero, who has 11 goals in his past 11 appearances. But it won't stop Guardiola from seeking out another attacker to increase competition and add more quality as he tries to build a side capable of competing for major silverware.
The defence is set for a major overhaul this summer, too, with several new arrivals expected at the Etihad. It won't be easy for any team to attract the absolute best with an apparent shortage of world-class defenders, which is why Juventus centre-back Leonardo Bonucci is City's No. 1 target even though it could be difficult to prize him away from the Serie A champions.
Bonucci, who turns 30 in May, is the perfect fit for Guardiola's team -- a solid, ball-playing defender with the leadership and experience to hold his defence together.
The City manager is huge fan of John Stones, who arrived in the summer, and has high hopes for the England defender after he initially struggled following his £47 million move from Everton. And there are hopes that there is still a future for captain Vincent Kompany, who has started just four Premier League matches this season after persistent injury problems. But Bonucci has been at the peak of his game for the past few campaigns for both club and country, to such an extent that Guardiola labelled him "one of my favourite-ever players" when he was in charge at Bayern Munich.
His qualities were clear to see on Wednesday night as Juventus became just the third club in Champions League history to shut out Barcelona over two legs. Collectively, the Serie A leaders are probably the best defence in the world and there wasn't much danger of a repeat of the way that Paris Saint-Germain embarrassingly buckled at the Camp Nou in the previous round when they were beaten 6-1 to relinquish their brilliant first-leg victory.
Juventus held a strong 3-0 advantage from their first leg in Turin eight days prior, but this time Lionel Messi, Neymar and Luis Suarez could find no way through a black and white wall -- the latest in long tradition of great Serie A defences.
Bonucci thrived with his defensive responsibilities and it was an example of intelligent ball-winning rather than panic tackling, as the Juventus defenders expertly marshalled Barca's threat.
It's a contrast to life at City, who can be in danger of conceding even when they are in complete control. Even in a convincing victory over Southampton at the weekend, City's defensive shortcomings were exposed.
In a first half where they dominated the ball and territory, Guardiola's men were almost undone by a simple break as the defence failed to cope. When Nicolas Otamendi gave away a stray pass midway through the period, Southampton raced to the other end of the pitch to create a good opportunity for Dusan Tadic, who could only fire wildly over the bar.
City got away with it and went on to win comfortably 3-0 and secure all three points, which could be crucial in their attempts to secure a top-four place and Champions League football for next season. But they haven't been as lucky in the past with opponents taking advantage of rare opportunities to steal point and cause serious damage to City's Premier League title hopes.
Top two Chelsea and Tottenham Hotspur ruthlessly exposed the defensive problems when they visited the Etihad in games that City dominated. Chelsea scored three times from four shots on target in a 3-1 win, while Spurs converted their only shots on target in a 2-2 draw with Stones, Otamendi and Aleksandar Kolarov all bullied by their opponents.
Asked about a potential new defender, Guardiola admitted at the start of the month: "The defender has to be rougher and tough. You cannot compete with strikers like [Romelu] Lukaku, [Zlatan] Ibrahmivoic, [Diego] Costa. You have to be like that. We are looking for not just that, there have to be qualities of a player, for us it's so important."
Bonucci fits the profile perfectly and after hinting that he might be interested in a move to the Premier League, Guardiola could just get the man he desperately needs.
Jonathan is ESPN FC's Manchester City correspondent. Follow him on Twitter: @jonnysmiffy.