Sunderland kept the pressure on the Nationwide Division One pacesetters after victory over Derby, although it should have been by a much bigger margin.
Argentinian defender Julio Arca was instrumental in both Black Cats goals and marked his first game since the FA Cup win over Sheffield United with a classy
display before being replaced by Colin Cooper with 14 minutes to go.
His powerful left-foot drive proved too hot for Derby keeper Lee Grant to
handle and John Oster was on hand to give Sunderland a 31st-minute lead and Arca
then picked out Tommy Smith from 40 yards for the striker to head the hosts two
goals in front five minutes into the second half.
Derby, who had never looked like salvaging anything from the game, were handed
a lifeline by Ian Taylor's 64th-minute penalty but Mick McCarthy's men took the
three points they deserved after a dominant display and underlined their
promotion credentials.
Sunderland skipper George McCartney shook off the ankle knock he picked up in
the midweek win over Gillingham to make his 41st-consecutive start but he was
adjudged to have handled in the area which gave Derby their penalty.
But the hosts were in control from the moment Arca picked out Gary Breen with
a fine first-minute free-kick although his header flew over the bar.
Moments later, Byfield flashed a drive from the left side of the penalty area
just wide of Lee Grant's upright.
Derby, stunned into action by Mick McCarthy's men, responded through Leon
Osman's long-range effort and then Jeff Kenna, who was a doubt prior to kick-off
with a back problem, tested Mart Poom with a free-kick.
But Sunderland had plenty of chances to break the deadlock before Oster
scored.
Arca latched onto Darren Williams' 10th-minute cross but Grant reacted
brilliantly to punch clear and Oster shot wide from the edge of the box four
minutes before he scored.
Derby's best chance of the half fell to Manuel Manel, who missed the target
from close range in the 33rd minute.
Osman also went close a minute before the break - but the strugglers almost
went 2-0 down on the stroke of half-time when Arca crossed for Paul Thirlwell
but he fired wide.
Thirlwell's miss was quickly forgotten when Smith looped a header over Grant
to extend Sunderland's lead in the 50th minute but Derby hit back with a Paul
Peschisolido effort and then Taylor scored the penalty that gave them hope.
If Sunderland were rocked by the goal, it did not show, as McAteer provided
crosses for Smith and then Arca to regain the home side's two-goal cushion but
they headed high and wide.
To their credit, Derby improved during the last quarter and Taylor had a
glimpse of goal following a scramble in the Sunderland penalty area but he
blasted wide.
Sunderland: Poom, McCartney, Babb, Breen, Williams,
Arca (Cooper 76), Thirlwell, McAteer, Oster,
Tommy Smith (Piper 81), Byfield (Stewart 75).
Subs Not Used: Thornton, Myhre.
Goals: Oster 31, Tommy Smith 50.
Derby: Grant, Boertien, Johnson, Mawene, Edwards (Bolder 45),
Taylor, Huddlestone, Kenna, Osman, Peschisolido, Manel.
Subs Not Used: Oakes, Costa, Walton, Labarthe Tome.
Goals: Taylor 64 pen.
Att: 30,838
Ref: G Salisbury (Lancashire).