Chesterfield manager Paul Cook praised his side's level of commitment as they racked up their third League Two win in a week, 1-0 at plummeting Plymouth.
Despite being under the cosh for most of the match, Cook's decision to introduce Luis Boa Morte and Jack Lester proved decisive.
Boa Morte crossed from the left, Lester chested the ball down and Marc Richards smashed the 66th minute winner and his second goal in five days after scoring in Tuesday's 4-1 home win over Cheltenham.
Cook said: "As you go through games, levels of performance are important. Today we put in a level of performance that was more through commitment than anything. We are delighted again. Three points in this league for any team on any day is always a great achievement.
"We weren't good in the game, we were never really moved the ball as well as we did the other night against Cheltenham but we certainly had no lack of commitment and effort. That was the pleasing thing about today because Plymouth were good value for a point.
"Make no bones about it, Plymouth were very hard done by today. We accept that, but that happens in football. Plymouth put us under immense pressure, that's why we went 4-4-2 when it was 0-0 to try and win the game.
"I am not a tactical genius but what we do is evaluate a game and make decisions that we think may alter the game. Today I was able to put Luis Boa Morte on at half time, how lucky am I as a manager?
"You would not expect any difference from Marc or Jack Lester, when they get in those positions we know they will score goals. If we put supply in the box we know they will score."
Plymouth had an effort cleared off the line and hit the bar in the first half and with the score at 1-0 had a penalty appeal turned down after substitute Joe Lennox's cross appeared to be handled by a Chesterfield player.
Plymouth boss Carl Fletcher rued: "I know I sound like a broken record but again we have dominated the game in every sense - chances, attempts at goals, possession and corners - but it just didn't bounce for us again today. It seems to be the way we are going. All the hard work we put in just isn't coming of for us."