* Ecuador substitute Arroyo strikes stunning late equaliser
* Sterling and Valencia see red after fracas in 2-2 draw
* England's Oxlade-Chamberlain suffers knee injury (Writes through with quotes)
By Ken Ferris
MIAMI, June 4 (Reuters) - An experimental England side gave a decent performance in a 2-2 draw with Ecuador who equalised through a superb strike by substitute Michael Arroyo before both sides were reduced to 10 men in an incident-packed World Cup warm-up match on Wednesday.
Arroyo had not been on the pitch long when he unleashed a fierce right-foot drive from 20 metres in the 70th minute that gave goalkeeper Ben Foster no chance after Rickie Lambert had put England 2-1 in front following a mazy run by Ross Barkley.
But tempers frayed nine minutes later when England's Raheem Sterling, who replaced Wayne Rooney just past the hour, flew into a tackle on Antonio Valencia. Ecuador's captain retaliated by grabbing Sterling around the neck and both were sent off.
"It (Sterling's red card) was harsh. It was a rash tackle but I thought Raheem was unlucky because of the way Valencia reacted like he did," England coach Roy Hodgson told reporters.
"I'm disappointed that a senior player like Antonio reacted in that way, but Raheem will learn from that."
There were also concerns over Alex Oxlade-Chamberlain, who suffered a knee injury and is set to have a scan on Thursday with Hodgson saying he may have suffered ligament damage.
Rooney, the only England player retained from the 3-0 win over Peru on Friday, had equalised from close range just before the half-hour after Ecuador had taken an eighth-minute lead when Enner Valencia powered home a close-range header.
"It was a very young lineup and there was almost a complete 11 players rested from the previous match," added Hodgson. "But I thought we acquitted ourselves quite brilliantly and played some very good football at times."
Both teams made wholesale changes with Hodgson casting his eye over an experimental lineup while Ecuador's Reinaldo Rueda made five alterations from the team that lost 3-1 to Mexico on Saturday.
Ecuador, who had won only two of their previous 13 matches, looked lively in the opening exchanges and took the lead when Enner Valencia got above Chris Smalling to head home after a fine left-wing cross by Walter Ayovi.
Rooney, who kept drifting into the middle from an unfamiliar role on the left, brought England level after 29 minutes when he fired into the net after Lambert, who appeared to have first handled the ball, saw his cheeky back-heel rebound off the post.
Both World Cup finalists made multiple substitutions but it was England who went ahead through Lambert's low drive after the impressive Barkley sliced through the Ecuador defence.
A lean-looking Rooney, who despite scoring his 39th goal for England never really stamped his authority on the match, was withdrawn after 64 minutes and replaced by Sterling.
Ecuador were chasing an equaliser and almost got one when Enner Valencia's mis-hit shot hit the post and they eventually levelled through Arroyo's wonderful strike 20 minutes from time.
England, who face Italy, Uruguay and Costa Rica in World Cup Group D, will play a final warm-up game against Honduras in Miami on Saturday before they leave for Rio de Janeiro.
Ecuador return to Quito to prepare for their opening match against Switzerland in Group E before they face Honduras and France. (Editing by Ed Osmond)