An out-of-sorts Atletico Madrid needed more than 80 minutes to break through against last-place Levante Saturday night in the Vicente Calderon, but substitute Thomas produced a bit of individual brilliance to lift his club to a 1-0 triumph that allowed them to go top of La Liga.
Barcelona, which trails by two points after drawing earlier in the day against city rival Espanyol, do have a match in hand over Atletico and third-place Real Madrid who trail Atletico by five points ahead of Sunday's game at Valencia.
Thomas got Atletico over the line when he snapped up a neat Gabi pass 30 meters out in the center of the field, swept to his left to stride past three defenders, then cut right before shooting low and hard enough to beat the dive of Levante's Diego Marino.
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It was a fine piece of finishing that sent the hard-working visitors to defeat when it appeared that the combination of their effort and Atletico's lack of form might allow them to grab a most-unexpected point. Levante remain bottom with 11 points and only two victories from 18 matches.
With five matches in two weeks thanks to their holiday midweek match last Wednesday and a two-legged Copa del Rey round-of-16 tie against Rayo Vallecano, Diego Simeone rested some of his regulars and almost paid the price.
Fernando Torres, seeking his 100th Liga goal but who has not scored since Sept. 19, was a notable on the bench while Jackson Martinez got another chance to make an impression at his new club.
Although Simeone ultimately used all three of his substitutes in an attempt to get Atletico's attack firing, Torres was not summoned for duty.
Instead Luciano Vietto spelled Angel Correa, Yannick Carraso replaced Koke, and , finally, match-winner Thomas came on for Jackson Martinez. Antoine Griezmann went the full 90 minutes but did not get the service he needed to be truly involved.
The visitors from Valencia defied their bottom-of-the-table status with a composed, defensively-tight performance that kept Atletico under control and often unable to dictate the match. Atleti's Martinez did bring a good save from Marino and Stefan Savic headed off the crossbar from a 28th minute corner and the hosts had much what passed for opportunities, but there was no bite far too often.
In fact, Levante's Verza, who came open at the top of the box only to shoot past the left post, had perhaps the best chance of the opening 45 minutes on the half-hour.
Atletico came out on the front foot after the interval and had Levante under pressure. Jackson Martinez had a header fly wide of the left post, then Koke had a 20-yard drive that beat Marino but smacked off the crossbar. Gabi had a cross from wide right clip the crossbar as the match approached the hour mark with Levante still frustrating the home side.
Levante wasn't entirely defensive, breaking when they could and forcing Atletico to stay honest in their own half. While Jan Oblak was not really troubled in goal, Jordi Xumetra had a couple of decent efforts that defenders had to block away. It appeared they might be able to hold out until Thomas put things right for the hosts.
Atletico opens their Copa del Rey tie Wednesday at Rayo, travels to Celta Vigo next Sunday, then faces Rayo in their second match Jan. 13 in this busy spell. Already out of the Cup, Levante will continue their fight against relegation against second-bottom Rayo Vallecano next Saturday.