Arsenal are number five on the points table, having 22 wins and 72 points in their kitty.
Sanchez tapped the ball in for his second goal of the day, and once again giving Arsenal another thin hope of making the top four in the English Premier League.
Arsene Wenger has blamed Arsenal's away record for their failure to match Chelsea in the Premier League title race.
They made heavy weather of their task, with Sanchez scoring a close-range double inside the final 17 minutes to secure the points with a 2-0 win.
Relegated Sunderland were showing some surprising resilience but Sanchez broke the deadlock in the 72nd minute, finishing off a flowing move by converting Mesut Ozil's pass.
'We won more games than last year because we already have one point more than last year, ' he said.
'Especially at Everton, we were really unlucky at Everton, some of the decisions were really bad on the night and after we had to go straight to Man City and it didn't help.More news: SC experts say GOP health care bill likely to affect you
"When you have a player like this in your team, to show the way we want to grow together, it is important and I think he has a lot of players behind him to keep him". We didn't play well on Saturday, we know that but I think you can see Sunderland had a go, tried to score at times but we were outclassed by a better football team. "You want all the teams to fight like Sunderland did tonight and, after, you have to accept the result".
"At the moment let's focus".
We had plenty of shots on goal but we needed to be patient.
"No, it's Tuesday night against Sunderland, everyone expects us to win", he said.
At the conclusion of a season that only served to underline how far Arsenal have declined in recent years, Wenger knows missing out on the top four would be the last straw for a large section of his club's disenchanted support.
Arsenal's victory, thanks to a late brace from Alexis Sanchez, keeps alive their hopes of sneaking into fourth place on the final day of the season.
"We had a hard patch after the Bayern game because it was hard to recover".