Tevez, Vermaelen among the season's best transfer purchases

With a week left on the Premier League clock, thoughts are starting to turn to the wheeling and dealing that the coming months will bring. Fernando Torres' scowl from the stands at Anfield on Sunday, as he watched his teammates surrender to Chelsea's endeavor, suggested his agent's phone would be buzzing before the weekend was up. The order in which the top six or seven teams finish -- not to mention the World Cup -- will help shape this summer's wish lists, so for now let's consider how the last year's signings have made an impact -- or not.

From big-money commitments to canny loan deals, here's the pick of the most influential moves since last summer's transfer window opened (in order of expenditure):

Carlos Tevez ($38.5 million) and Adam Johnson ($10.6 million), both Manchester City

By almost every measure you can come up with, Tevez has been the season's star buy, adding 29 goals and a scampering urgency to City's frontline. The only thing spoiling the love-in is his insistence on criticizing Roberto Mancini's training methods. No such complaint from Johnson, whose arrival from the Championship-side Middlesbrough has helped to make a potentially threatening attacking lineup damn near dangerous.

Darren Bent, Sunderland ($15.3 million)

It's no secret that I've been impressed with Bent this season. The former Tottenham striker must have been down to his last few bags of self-confidence by the time Steve Bruce showed an interest last summer, but it took him just five minutes to open his Sunderland account with a winner against Bolton. Without his goals, Sunderland would be a massive 19 points worse off this season. Injury might have mitigated their impact as a duo this season, but Bruce also gets a nod for the signings of midfielders Lee Cattermole and Lorik Cana.

Thomas Vermaelen, Arsenal ($15.3 million)

Vermaelen is the most expensive defender Arsene Wenger has ever signed for Arsenal, but this wasn't a rush of blood to the head after cashing the check from Manchester City for Emmanuel Adebayor and Kolo Toure. At a club where potential is given time and space, the Belgian's instant success in the centre of defense (from where he's also scored eight goals) has been a tonic. Wenger also broke with habit by re-signing Arsenal old boy Sol Campbell this year. He's been necessary cover, as it turns out, and adequate enough to have convinced Wenger to buy a couple more experienced players this summer.

Richard Dunne, Aston Villa ($7.6 million)

Martin O'Neill spent around $60 million last summer, if the newspapers are to be believed, but he's proved himself a discerning shopper: Stephen Warnock, James Collins and Stewart Downing (who unleashed a scorching right-foot shot that skimmed the outside of the post in the defeat to Manchester City on Saturday) have all established themselves in Villa's first XI with accomplished seasons. Dunne tops the list of new arrivals with a rock-solid campaign -- and he's contributed the odd goal to boot.

Chung-Yong Lee, Bolton ($3.4 million)

It's not often Koreans pitch up in the Premiership, let alone make a good impression, but Lee has been one of the most exciting new players this season. Despite falling asleep on the bench during his first match, Lee's nimble feet and agile mind have been such a hit on the Bolton wing that Liverpool is reported to be offering a quick $9 million profit this summer.

Jamie O'Hara, Portsmouth (loan)

Despite being on loan, O'Hara has played like a Pompey fan born and bred, charging around the midfield with scant regard for his blood pressure. No other Portsmouth player has provided more assists, or a lovelier goal than that he curled in against Hull back in March. Harry Redknapp could have done with him back when injury hit Spurs, but Niko Kranjcar wasn't a bad January signing either.

Landon Donovan, Everton (loan)

Rarely can anyone have adjusted to the Premier League in so brief a time and with such composure -- Everton manager David Moyes was desperate to extend Donovan's stay at Goodison Park after just 13 appearances. Los Angeles was having none of it, and who can blame Galaxy coach Bruce Arena? Donovan might shirk the odd challenge but always puts in a shift and has pace to burn. He was a natural fit for Everton, who should beat others to his signature in the summer.

With the good, must come the bad. Until a few weeks ago, Alberto Aquilani would have been the first name on anyone's list in this category. Signed by Rafael Benitez for $30 million from Roma while still injured (ankle), his limited contribution to Liverpool's season seemed to sum up Anfield's malaise. An 11th-minute scorcher that skimmed the top of the bar aside, he was as ineffective as anyone in a Liverpool shirt against Chelsea this weekend. But recent performances have given more than a hint of what Rafa signed up for: with six assists, he's now only one behind Steven Gerrard, the club's top provider. Knowingly signing an injured player for $30 million still isn't too sensible, but it could have been worse:

Joleon Lescott, Manchester City ($33.6 million)

Lescott's dismal start to life at City -- having mangled Everton's early season with his protracted move -- wins out as the biggest flop. In fairness, the ransom demanded by Moyes, who wanted Lescott to stay, put enormous pressure on the young England pretender to perform. But even if he'd stayed fit, he rarely looked like justifying the fee.

Roque Santa Cruz, Manchester City ($26.7 million)

It's almost too easy to pick on City, whose interest in anyone automatically sends the asking price through the roof. But Santa Cruz's haul of three league goals and zero assists (even Lescott's got one) puts him right in the firing line. While his lustrous mane has grown considerably, the same cannot be said for his reputation. Last summer he was being linked with Spurs and Liverpool; this summer, newly promoted Newcastle is hoping to pick him up on the cheap.

Jason Scotland, Wigan ($3 million)

One league goal in 31 appearances suggests you can take the player out of the Championship, but you can't take the Championship out of the player; Scotland scored 21 in that division for Swansea last season. If you're a striker being outscored by bungling defender Titus Bramble (two goals), you know you're having a bad season. There is almost constant speculation that Roberto Martinez will be relieved of his duties as manager at the season's end, and it's worth a wager that Scotland will be shipped out too.

Mido, West Ham (loan)

The guy's so desperate for a game that he's playing for $1500 a week, peanuts by Premier League standards. A peanut. But goodwill only stretches so far, and Mido's failure to contribute to West Ham's goal count since arriving in February hasn't gone down well with the fans. Especially having missed a penalty against Everton when relegation was still very much on the cards. The overweight Egyptian didn't help his cause when he was caught scoffing a large portion of fish and chips by a Hammers bigwig within a month of arriving.

Unsurprisingly, Mido wasn't in the West Ham squad to face Fulham this weekend. Jonathan Spector might wish he hadn't been, after a spot of hapless defending allowed Erik Nevland to set up Stefano Okaka for Fulham's winner. A better afternoon for Clint Dempsey, though -- he opened the scoring and might have had more as he zipped about the pitch. Brad Friedel and Marcus Hahnemann both conceded three goals, a stat of more consequence for the Aston Villa keeper, who misses out on a shot at Champions League football. Tim Howard kept a clean sheet, but then he only had three shots from Stoke to handle.