3 Chelsea Loan Stars Who Could Make Jose Mourinho's Squad Stronger

Chelsea will sign three players this summer, or at least try to, according to Jose Mourinho.

"I want a striker, because we lost our legend [Didier Drogba]," he said at the launch of BT Sport's European football channel for 2015/16, per International Business Times. "[We also need] a defender and a midfield player to give a little bit more competitiveness to the squad, bring some new blood in, put some players a little bit under pressure."

Well, before Chelsea look elsewhere, they could assess some of the 25 players they had out on loan this season.

Do the maths and, yes, that's the equivalent of a Premier League squad that Chelsea had dotted around the continent playing for other clubs.

Of course, we know Chelsea have used the loan system to increase the value of players with a view to selling them on, such as Kevin De Bruyne, who joined Wolfsburg for a big profit in January 2014.

But then, Thibaut Courtois and Kurt Zouma have bucked the trend in more recent times—being two players who have spent time away from Chelsea before becoming a big part of the first-team squad.

Are there any others who could emulate their success?

Ignoring some of the better known players such as Patrick Bamford, Bleacher Report highlights three loan stars who could prove useful to Mourinho next season.

Tomas Kalas

Position: Defender

Age: 22

Loan club: FC Cologne/Middlesbrough

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It was a difficult season for Kalas last year. He spent the first half of the campaign in Germany with FC Cologne, before joining Middlesbrough on loan in January.

While with Cologne, he made just seven appearances in all competitions, although, things did improve at Boro, where he featured 17 times.

In terms of standing out to show Jose Mourinho that he is capable of making the grade at Chelsea, his time away from Stamford Bridge wasn't ideal.

With Boro chasing a place back in the Premier League, Aitor Karanka preferred his more experienced centre-backs, meaning much of Kalas' appearance time was in the first few months of his Riverside spell.

When things got serious, he was hooked.

And when he was performing to his best, Kalas picked up an ankle injury that impacted his form.

The past 12 months have been typical of the pitfalls many loan players can experience. Away from their parent club, some struggle to adapt to their new surroundings, knowing it's only a temporary move.

There's also adapting to a different style of play, adjusting to the fact those around them aren't of the same quality they play with at Chelsea.

For a defender, that can be daunting. It can leave them exposed more, and with one bad performance, things can go downhill pretty quickly.

We've seen little of Kalas in a Chelsea shirt—he's featured just four times. Two of the appearances were starts, while the other half came as a 90th-minute substitute.

Michael Regan/Getty Images

It's his Premier League debut that stands out, however. Kalas was faultless against Liverpool when Chelsea traveled to Anfield with a depleted team in April last year.

The game is remembered more for Steven Gerrard's slip that allowed Demba Ba to score, but Mourinho will do well to remember how impressive Kalas looked.

Sure, it's one performance in isolation, yet it hinted to so much more.

Mourinho doesn't need to find a starting centre-back this summer. Instead, he needs another player to play the back-up role to John Terry and Gary Cahill, one that Kurt Zouma performed so well last term.

Kalas fits the mould.

He's had the set-back of a disappointing season away from Stamford Bridge, but Zouma's example is the one he can follow.

Mourinho says so himself—the Frenchman was lacking in his tactical nous when he arrived at Chelsea. He was a raw talent, but one that has been nurtured by the manager's coaching methods.

Rather than spending money in an area where Chelsea remain strong, Mourinho can strengthen his reserves by making Kalas a more permanent fixture in the first-team squad.

Lewis Baker

Position: Midfielder

Age: 20

Loan club: Sheffield Wednesday/Milton Keynes Dons

Paul Thomas/Getty Images

So often in 2014/15 we saw Lewis Baker on the Chelsea bench, but for one reason or another, he never got the opportunity to make his Premier League debut.

By the time Chelsea had won the title and Mourinho was willing to give his youngsters more game time, Baker was on loan.

That shouldn't deter him, however. If anything, he should be feeling positive after a promising spell with Milton Keynes Dons.

Baker also spent a brief spell with Sheffield Wednesday in January, but it was under Karl Robinson where he shined, helping the Dons secure promotion to the Championship.

The 20-year-old didn't play a small part, either. He was involved in some special moments, scoring three goals, including a pearler against Notts County.

It's easy enough to point to the level of opposition Baker was facing in League 1. Yet as we've seen so many times, it's one thing playing lower than the leagues and quite another to perform.

His goal against Notts County demonstrated everything that's positive about Baker's game. He spotted the space to run into and exploit a stretched defence. Not only that, he kept his composure to fool the goalkeeper.

Any Chelsea fans taking notice of the club's academy games wouldn't have been surprised. Goals of that class have been a forte of Baker's time with the development squads.

Similar to Kalas, Baker isn't going to be starting games at Chelsea next season should Mourinho promote him. And again, Mourinho isn't looking for players to do that.

This Chelsea team all but picks itself. The gaps that remain are in the squad, and given that Chelsea used the least number of players in the Premier League last season, it's clear there's a need to add numbers that allow for rotation.

That can come in the cup competitions and also in matches when Chelsea have already secured the three points.

It's how youngsters of Baker's ilk should be integrated into the picture at any big club. It's too much to expect them to match the likes of Eden Hazard. But equally, they need to gain experience.

Baker can play anywhere across the three attacking midfield positions, and his presence would certainly give Mourinho options throughout 2015/16.

Oriol Romeu

Position: Midfielder

Age: 23

Loan club: Stuttgart

Dean Mouhtaropoulos/Getty Images

Take Cesc Fabregas out of this Chelsea team and what do they lack? A player capable of keeping possession and bringing others into play.

Oriol Romeu isn't quite as talented as his compatriot in that regard, but hailing from the same school as Fabregas, he remains capable enough.

Romeu is a product of Barcelona's famed youth academy, and watching him play, it's evident.

He'll turn 24 in September and is now reaching an age where he needs to deliver on the potential he undoubtedly has.

Romeu did that to some degree while on loan with Stuttgart in the Bundesliga last term, enjoying a passing average over 80 per cent during the course of the season.

For a player in a team that avoided relegation by the odd point, it's a stat not to be scoffed at.

Romeu is a cultured midfielder, one capable of offering Chelsea something they haven't already got.

Ruben Loftus-Cheek is going to be a big figure next term, and backing him up should be Romeu.

Ben Hoskins/Getty Images

Again, he isn't going to be starting many games, but Romeu would be an upgrade on John Obi Mikel, a player who is Mourinho's go-to guy when it comes to attempting to lock down games.

The sight of Mikel must frustrate teams, as it's clear where the game is going when Mourinho brings him on. Chelsea are often leading and the plan is to kill the game off.

Given Mikel's shortcomings, he can actually have the opposite impact, as we saw at Old Trafford last season when Manchester United grabbed a last-minute equaliser to draw, 1-1.

Chelsea had been in control, but when Mikel came on, they seemed erratic in possession, and it gave United the impetus to attack.

Romeu's ability to retain possession—not to mention his superior passing skills to Mikel—marks him as a better alternative.

He's been at the club for four years now, but his career hasn't taken off in the way some might have imagined. Romeu only signed a new contract last summer, too, so his long-term future is at Stamford Bridge.

Mourinho could do much worse than utilise his talents to bulk his squad and freshen things up in a key part of the pitch.

*Stats via ESPN FC and WhoScored.com.

Garry Hayes is Bleacher Report's lead Chelsea correspondent. All quotes were obtained firsthand unless otherwise noted. Follow him on Twitter @garryhayes