"These last few outings I haven't done a very good job," Lyon said. "I've just got to make better pitches."
A win would have given the D-backs a two-game lead in the division. Instead, the division is now where it was on Friday -- a virtual deadlock.
It was Lyon's third straight day on the mound. After throwing 12 pitches Friday and 28 on Saturday, Lyon said he was perfectly comfortable with going out to pitch for a third consecutive day and said his recent pitch count had nothing to do with how he performed on Sunday.
Lyon (2-4) ended up throwing 27 pitches in his blown save, allowing five runs in two-thirds of an inning. His ERA after Friday was 2.37, lowest among all relievers on the team by more than half a run. After Sunday, it skyrocketed to 3.86.
"His stuff was there, he just wasn't locating," D-backs manager Bob Melvin said. "He was getting behind and they got some good at-bats off him. Kemp's at-bat was a good at-bat. We had all the pieces going into the ninth inning and they ended up fighting hard."
Brandon Webb was denied his Major League-leading 14th win. The D-backs' ace threw a gem, allowing just one run on six hits in eight innings, throwing 109 pitches.
In the eighth inning, the Dodgers had runners at first and second with one out. Melvin came out to talk to Webb but ended up not taking him out. Webb ended the inning with a 5-4-3 double play by Kemp.
"I worked out of some jams, made some pitches when I had to and came out pretty much unscathed," Webb said.
The D-backs' bullpen is like night and day from 2007, when the team was a Major League-best 32-20 in one-run games, despite being outscored on the season by 17 runs. This season, the club is 14-15 in one-run games.
Last year's closer, Jose Valverde, was 47 out of 54 in save opportunities and this year leads the National League with 25. Lyon has 20.
"This is his once out of 10. He'll be fine and come back tomorrow," Webb said.
"There isn't a night that I wouldn't feel comfortable with Brandon on the hill," first baseman Tony Clark said. "Tonight it didn't work out. We'll wash our hands. I'm sure he washed it off in the shower."
The Dodgers ended up batting around in the ninth, compiling six hits -- four of them consecutively and with two outs for the go-ahead runs.
With runners at first and third and none out, Andruw Jones hit a slow roller up the middle fielded by shortstop Stephen Drew, who bobbled the would-be double-play ball as he got only the one out at first base. The next batter grounded out, but still three more runs crossed home plate.
"It's just one of those things where you try to get the out at second, not trying to do too much," Drew said. "[It took] a bad hop. Thankfully, I got him at first. I didn't even think I had a chance there at the end."
Drew did have a good day at the plate, going 4-for-5, including a triple. He followed a sign from third-base coach Chip Hale to try for an inside-the-park-homer, but was thrown out at the plate, thanks to a good relay from Jones and shortstop Nomar Garciaparra.
Drew also tacked on an RBI single with two outs in the bottom of the ninth to plate the D-backs' fifth run.
The D-backs scored three times in the first inning after Drew and Conor Jackson led off with consecutive singles.
Arizona scored again in the sixth inning. After Mark Reynolds tripled, he scored on a suicide-squeeze play started by catcher Chris Snyder, who returned from the 15-day disabled list.